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Forewarned is forearmed...

IDE, SATA, SCSI Hard Disk Drives, SSD, CD/DVD and Blu-ray drives - Page 1

Last updated on 12 May 2008

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CONTENTS

This section of the site consists of three pages. Click the relevant link to visit the following topics. - Use your browser's Back button to backtrack.

Hard Disk Drives - This Page - Scroll down the page

Hard Disk Drives - Page 2

CD/DVD Drives - Page 3

Floppy & Zip Disk Drives - Page 3

USB Flash Drives

Click here! to go to information on this site on USB Flash Drives

OTHER INFORMATION ON HARD DISK DRIVES ON THIS SITE

HARD DISK DRIVE PROBLEMS AND SOLUTIONS

Click here! to visit the pages on this site devoted to hard disk drive problems and their solutions.

HOW TO INSTALL A HARD DISK DRIVE

Click here! to go to the page on the Build Your Own PC section of this site that deals with installing hard drives.

HARD DISK DRIVES: UPGRADE CHECKLIST

Click here! to go to information on this site on what you need to consider when upgrading a PC's hard disk drive.

An introduction to hard disk drives

Internal hard disk drives

An IBM  IDE hard disk drive

Almost every modern desktop PC or laptop/notebook PC contains at least one internal hard disk drive (HDD) as the permanent mass storage device for its software.

Some desktop and laptop PCs now use flash memory or a Solid State Drive (SSD) flash-memory drive instead of a hard disk drive, but they are currently exceptions to the rule because flash memory currently costs much more than hard-disk space.

Flash memory is also used in solid-state drives (SSD) that can be used in desktop and laptop computers instead of conventional hard disk drives. An SSD drive uses much less power than a conventional hard drive, and it can withstand shocks (when a laptop is dropped, etc.), better than conventional hard drives. At the time of writing (May, 2008), the capacities of SSD drives have reached 128GB, although only 32GB SSD drives are currently inexpensive enough to make them a viable alternative to standard hard disk drives.

In the near future, as the prices of flash memory and flash-memory devices reduces compared to the prices of current means of data storage, it is likely that all PCs for home use will use flash memory instead of RAM memory, and SSD drives instead of hard disk drives.

Memoright SSDs: The End of Hard Drives? -

"Memoright has achieved an important milestone with its flash SSD: the device’s performance is truly better than that of any competing hard drive." -

http://www.tomshardware.co.uk/ssd-memoright,review-30808.html

Memoright - http://www.memoright.cn/en/

Most desktop PCs currently use 3.5" hard disk drives. Most laptop PCs currently use the smaller 2.5" hard disk drives especially designed for use in mobile, portable computers.

Visit the Desktop PCs section of this site for information on how to buy, build, repair, fix, and protect the various types of desktop PCs.

Visit the Laptop/Notebook PCs section of this site for information on buying and protecting them, and fixing problems with them.

When the computer is switched off, the software and data files, etc., remain recorded on the hard disk drive's magnetic platters, and can be accessed by the operating system the next time the computer is switched on.

All modern PC motherboards have the capacity for at least four IDE ATA disk drives, which could be a mixture of hard disk drives and CD/DVD, or Zip drives and LS120/LS-240 super floppy disk drives, which can use the IDE bus. IDE ATA is outgoing technology. The current motherboards that support the latest serial ATA (SATA) standard usually provide connectors for six drives, which could be a mixture of SATA hard drives and optical CD/DVD drives.

The operating system (DOS, Windows, Unix, Linux, OS X, etc.), and all of the application software (MS Office, Internet Explorer, etc.) is loaded by an installation program on a floppy disk or CD/DVD disk on to the drive's magnetic platters for retrieval by the operating system, which, of course, has to be instructed to do so by the computer's human operator via the computer's keyboard and mouse, the computer's processor, and its RAM memory.

The RAM (volatile memory) cannot presently hold any data permanently, because it records the the bits of data (as the ones and zeros of the binary numerical system) as electric charges that disappear when the computer is switched off.

If you want to know the technical details of how a hard disk drive works, click the following link and then use your browser's Back button to return to this page. - http://computer.howstuffworks.com/hard-disk.htm

The best and most popular manufacturers of hard disk drives are Western Digital, Seagate, Maxtor (now owned by Seagate), Fujitsu, Samsung, and Hitachi. IBM used to make hard disk drives but sold that part of its business to Hitachi.

There are only three main standards used to interface internal hard disk drives, CD drives, etc. - the SCSI and IDE ATA standards (the IDE ATA standard is also called PATA, which stands for Parallel ATA) - which have been available for many years, plus the latest standard called serial ATA, usually abbreviated to SATA, which is available in two versions - SATA 150 (the first version) and SATA II 300.

The IDE ATA standard is also known as Parallel ATA (PATA), because it makes use of a ribbon cable that has 40 conductors that transfer data in parallel, plus another 40 conductors that shield them from interference for PATA 66/100/133 drives. Round cables are also available for use with these drives.

The Serial ATA (SATA) standard is compatible by design with the original IDE Parallel ATA (PATA) standard. In fact, they are so similar that accessory adapters are available that allow an existing PATA hard drive to plug into a PCI SATA controller card or the SATA connectors on a motherboard.

External hard disk drives

It is possible to buy hard disk drives (and other disk drives, such as floppy disk and CD/DVD drives) that connect to a desktop PC or a laptop PC externally via a USB, FireWire, or eSata connection.

Click here! to go to the information on external hard drives on this site.

SCSI hard disk drives

Click here! to go to the information on SCSI hard disk drives on Page 2.

Use your browser's Back button to backtrack.

External eSATA hard disk drives

Page 2 of this article deals with external hard disk drives.

How hard disk drives work

The following article provides an overview of how hard disk drives work:

Factfile: Hard disk drive -

"A hard disk drive is the device used to store large amounts of digital information in computers and related equipment like iPods and games consoles such as the Xbox 360 and PS3." - http://news.bbc.co.uk/1/hi/technology/6677545.stm

Anatomy of a Hard Disk Drive - http://www.hardwaresecrets.com/article/177

Recovering the data from a faulty hard disk drive

Testing the limits of hard disk recovery -

http://news.bbc.co.uk/1/hi/technology/6677235.stm

The faster, more expensive SCSI (Small Computer System Interface) drives and devices are often found employed in high performance PCs, but most often on non-PC platforms, such as Unix workstations and servers.

The second-named standard, IDE (Integrated Drive Electronics) ATA is much cheaper than SCSI and is still the most used of the three standards because it has been in use for over a decade. It has gained ground on the SCSI speeds of execution and data transfer.

The third standard, serial ATA (SATA), potentially the fastest of them all, could transfer data as fast as 600MB/s now, but the current internal mechanisms of hard drives limit it to being not much faster than standard IDE ATA drives, which can only sustain about 60MB/s in practice.

This situation was expected to be overcome by the SATA II 300 standard, but the drives that have become available that use it have not shown much of a performance increase over the earlier version of the standard (SATA 150), which, in turn didn't outperform the earlier Parallel ATA (PATA) drives.

SCSI technology had to adopt serial technology in order to keep ahead of the SATA II 300 standard, which has a theoretical data transfer speed of 300MB/sec compared to the 320MB/sec of the fastest parallel Ultra320 SCSI standard. The new serial SCSI standard is called Serial Attached SCSI (SAS).

Click here! to go to the information on SCSI hard disk drives on Page 2.

HARD DISK DRIVE NEWS

Samsung doubles the capacity of its solid state drive (SSD)

March 29, 2007. - Samsung claims to have doubled the capacity of its wholly electronic solid state drives (SSDs), which use NAND flash memory. The company has unveiled a 1.8" 64GB model. According to Samsung, the drive provides significantly higher performance compared to conventional SSDs. The read and write performances of the new drive have been increased by 20% percent and 60% respectively compared with the 32GB SSD drive that Samsung made available in 2006. The pricing and availability of the drive have not been announced, but that information should be made available some time this summer.

The new drives are designed for use in compact laptop/notebook computers, personal navigation systems, and digital camcorders. Because they have no mechanical parts, such as spinning platters, compared with traditional mechanical hard disk drives, solid state drives provide superior reliability, quieter operation, quicker data access, and drop-in replacement. Up until now, the only disadvantage of SSD drives has been their higher cost, but with tumbling flash memory prices, this is becoming less of an issue all the time.

Samsung, Sony, and Fujitsu have already marketed laptop/notebook computers that use solid state drives instead of traditional hard disk drives. Given that in January 2007, Sandisk announced a 32GB, 1.8" solid state drive (SSD), which was also marketed as a replacement for a standard mechanical hard disk drive in desktop PCs, it looks as if the latter type of drive will soon be superseded by SSDs in all computers.

Samsung makes its first hybrid hard disk drive available

March 7, 2007 - Samsung has announced that its first hybrid hard disk drives that use a combination of conventional hard-drive magnetic storage with flash memory are being shipped to dealers.

The drives that go under the name of FlashON, are designed for use in laptop/notebook computers and work with the ReadyDrive feature in Windows Vista.

Using ReadyDrive, the flash memory is used as a data cache that Windows Vista accesses instead of the slower hard drive, which improves efficiency and saves power. According to Samsung, the combination of a hybrid drive and ReadyDrive reduces power consumption in a laptop computer by 70% to 90%. Moreover, since data is stored and retrieved from flash memory more quickly than from a standard hard drive, the computer wakes up from sleep mode more rapidly. ReadyDrive is only available in Windows Vista, so computers running other versions of Windows or other operating systems won't benefit from using a hybrid drive.

The first three FlashON hybrid drives have capacities of 80GB, 120GB, and 160GB, which come with either 128MB or 256MB of flash memory. Samsung has already produced a prototype model with 4GB of flash memory. Drives incorporating that much flash memory will obviously be even more effective than the models that are being shipped to dealers.

Intel is developing its own hybrid system, code-named Robson, in which the flash memory is incorporated on the computer's motherboard. It will be included on Intel's new Santa Rosa laptop/notebook platform that is due for release in the second quarter of this year.

You can have a look at Samsung's ranges of hard drives, including the FlashON drives, on this page: http://www.samsung.com/Products/HardDiskDrive/index.htm.

Read Happy 50th, hard drive. But will you make it to 60?, which is an article on flash memory that includes information on the new drives, showing an image of one compared to the size of a laptop computer.

Google's surprise findings on hard-disk-drive failures

February 19, 2007. It has been widely assumed that heavy use and operating in high temperatures are the major causes of failures in hard disk drives. However, Google uses many thousands of off-the-shelf hard drives to power its search engine, and its findings point a low use and operating at low temperatures as being the main causes of hard-drive failure.

Read the full story here: http://news.bbc.co.uk/1/hi/technology/6376021.stm.

Windows Vista: Data storage

February 17, 2007. - Windows Vista has an improved file system, support for hybrid disk drives (H-HDDs), volume shrinking and volume extending, and drive encryption features.

"Microsoft also expects that H-HDDs will extend the lives of batteries and disk drive. Known as Windows ReadyDrive, H-HDDs cache disk reads and writes without needing to spin the disk drive. According to Hiroshi Sakakibara, product manager on the Windows client team, this saves battery power on the machine and can also prevent disk failures when using laptops while on the go. "Windows ReadyDrive makes your laptop more rugged since it is less likely the disk will be spinning and susceptible to damage as one is running from meeting to meeting", say Sakakibara." -

Five things you'll love about Vista's storage -

http://www.computerworld.com/action/...Basic&articleId=9004513

Windows Vista: ReadyDrive

"Windows ReadyDrive is a new feature in Windows Vista that enables PCs equipped with a hybrid hard disk—a new kind of hard disk that adds flash memory to a standard mobile PC hard disk drive—to enjoy better performance, greater reliability, and longer battery life."

"Windows Vista support for large-sector hard disk drives"

November 28, 2006. - "Hard disk drive manufacturers will soon start producing hard disk drives that contain physical sector sizes that are larger than the traditional 512 bytes per sector. For example, sectors may be 1 kilobyte (KB), 2 KB, or 4 KB. This change will enable manufacturers to improve the capacity, the performance, and the reliability of their hard disk drives. This article discusses Windows Vista support for large-sector hard disk drives." - http://support.microsoft.com/kb/923332

***

External SATA, or eSATA technology - http://www.sata-io.org/esata.asp - appears to be making its presence felt in the market. eSATA enclosures are becoming more widely available, and some motherboards offer built-in support for the technology. The hard drive enclosures operate much like USB and FireWire enclosures, but with much faster data transfer speeds. An enclosure for four drives containing 750GB Barracuda 7200.10 units provides a massive 3TB (3000GB) of disk space.

ExtremeTech has an overview of eSATA technology and a review of a LaCie eSATA enclosure. - http://www.extremetech.com/article2/0,1697,1953878,00.asp

Unfortunately, the IDE ATA standard has been given several confusing marketing names by the different concerns involved in the manufacture of IDE devices - E-IDE - ATA - Ultra ATA - DMA - UDMA - Ultra DMA.

To add to the confusion, because serial ATA (SATA) drives are now available, the older IDE kind that uses a parallel interface is now also called Parallel ATA or PATA. So, if you see a reference to a PATA drive, it means an IDE ATA drive.

See further down this page for information on serial ATA (SATA) hard disk drives.

Luckily, all you need to remember to be able to distinguish between the IDE and SCSI standards is that SCSI drives are daisy-chained together with special cables, and are usually, but not always, attached to a PC via an add-on card installed in one of the motherboard's ISA or PCI slots. - An SCSI controller chip can also be found integrated on some PC motherboards, but this is the exception, not the rule.

Both IDE ATA and SATA drives are usually attached directly to the motherboard by special ribbon cables.

The type of IDE ATA ribbon cable shown in the image below on the left can accommodate two drives each. There is a second connector that connects to a drive in the middle of the cable.

The ribbon cable shown in the image on the right is for a floppy disk drive. It has a twist in the conductors that is clearly visible at the end of the connector that must always be fitted to the floppy disk drive itself.

DE ATA hard disk drive ribbon cable that can connect two drives to the motherboard
Floppy disk drive ribbon cable

You can also purchase an add-on PCI card for an IDE ATA drive if you want to install more than the usual maximum of four drives - or if you want to use a higher mode of the standard not supported by the motherboard. Serial ATA (SATA) drives use thinner ribbon cables that can only accommodate a single drive. Look further down this page to see an image that compares the two types of ribbon cable.

IDE ATA (PATA) hard drives require to be connected to the power supply unit by one of its standard four-pin Molex power cables. Some SATA hard drives can use a Molex connector, but more recent models can require to be connected to the power supply unit by the newer SATA power connector, which is thinner than a molex plug. However, if an older power supply unit doesn't have an SATA power connector, a converter cable can be purchased for about £4 from a vendor such as http://www.maplin.co.uk/. It plugs into a Molex plug.

However, note that some new SATA drives require a +3.3V connection that old-style ATX 1.3 power supply units can't supply; they require to be connected to a new-style ATX12V 2.0 power supply unit. The user manual for a particular make and model of drive that can be obtained from its manufacturer's site should provide information on its power requirements.

Further, illustrated information on SATA hard disk drives is provided further down this page.

OEM hard disk drives

OEM stands for Original Equipment Manufacturer. The term has existed for a long time in the PC industry. PC 'manufacturers' such as Dell, HP, and Gateway are called OEM manufacturers even if they merely assemble computers using components made by other manufacturers. OEM drives can be sold by the actual drive manufacturer, or by a vendor such as an online store that sells directly to the public. Such a vendor can sell the fully-supported retail product that comes boxed with cables, software, screws, etc. However, an OEM hard disk drive is likely to be sold at a reduced price in bare, unmarked packaging, on its own (without cables, screws, etc.). Note that in some cases, an OEM drive is not even supported by the vendor. In some cases, you may even not be able to obtain firmware upgrades from the manufacture's website, which might be required in order to take advantage of the drive's maximum performance or its full set of features. Fortunately, hard drives are very cheap nowadays, so buying the fully-supported retail package (the recommended option) is easily affordable by most users.

Disk defragmentation: Free or inexpensive Disk Defragmenters (defraggers)

The files on hard disk drives run by Windows XP and Windows Vista don't fragment nearly as badly as those run by Windows 95/98/Me, but they still have to be defragmented in order to prevent a deterioration in system performance. The Windows Disk Defragmenter under All Programs => Accessories => System Tools for Windows XP and Windows Vista does an adequate job. Alternatively in Windows XP/Vista, open My Computer (just Computer in Vista), right-click on the drive that you want to defragment, click Properties, click on Tools, and then open Error-checking.

However, most third-party programs are superior. Here are two worth trying:

DIRMS from http://www.dirms.com/ is a superb defragmenter that runs in a command window under Windows.

The full commercial licence costs only $10 for use on up to five computers. The fully-functional freeware version requires a free license key obtained by registering on the developer's site. The freeware key works for 30 days, after which you can obtain another free key. If you don't want to register, you can use the software as freeware (no registration), but without access to some features and functions.

Ashampoo: Magic Defrag from http://www.ashampoo.com/. Automatically defragments hard drives while they are idle. Priced at only $12.95.

How to identify the make and model of the hard drive(s) installed in a PC

It is useful to know the make and model of a hard disk drive installed in a PC, because the manufacturer provides free diagnostic tools and utilities that partition, format, transfer data to a new hard drive, etc., which can only be used with its drives. If you don't know the make of the PC's hard drive, open the Device Manager by right-clicking on My Computer and then click on Properties in the menu that comes up. In Windows XP, do all of that and then click on the Hardware tab, or enter devmgmt.msc in the Start => Run box.

The devmgmt.msc command works in Windows Vista, but you have to enter it in the Search box, because Vista no longer has the Run box. Read What's changed from Windows XP? for more information on using Search in Vista. There are many other ways to open the Device Manager in Vista, such as under System and Maintenance in the Control Panel.

When the Device Manager is open, click on the + beside Disk drives to reveal the hard drive(s) installed. If the manufacturer's device drivers are installed, the make and model of each drive listed there should be provided. If the standard Windows drivers are installed, the make and model won't be provided. In that case, try entering msinfo32 in the Start => Run box in Windows 98 and XP. (In Windows Vista, use Search.) Doing that brings up the System Information window. Look for the information provided on disk drives. In Windows XP/Vista, the information is under Components => Storage => Disks.

Alternatively, use the free Belarc Advisor, which creates an analysis of the hardware and software on a personal computer - look for it under FREE DOWNLOAD at http://www.belarc.com/. When you know the manufacturer of the drive, if you don't know the web address, enter the name (Maxtor, Hitachi, Seagate, Western Digital, Samsung, etc.) in a search engine such as Google.

Windows 98 and Me and the original version of Windows XP do not natively support 48-bit LBA drives larger than 137GB

There are ways to make a hard drive larger than 137GB work with Windows 98 or Me, "...but you must work around some limitations and may likely need to upgrade components on your system in order to install and use your 48-bit LBA hard drive with Windows 98 or Me. Adding a 48-bit LBA hard drive for use with Windows 98 or Windows Me is the most complicated scenario compared to other more recent Microsoft operating systems such as Windows XP." For the information on how to use a large hard drive in Windows 98 and Me, visit this page. -

48-bit LBA and Windows 98, 98 SE, Me - http://www.48bitlba.com/win98.htm

For more information on the 137GB barrier, click the following link to download a PDF file on the subject. - http://www.seagate.com/support/kb/disc/tp/137gb.pdf

Note that the above information is not applicable to Windows Vista, which supports drives larger than 137GB.

Note that there are two types of IDE ribbon cable. The earlier type of cable is used on ATA HDD drives running ATA (UDMA) 33 and earlier ATA modes. This cable has 40 conductors in the ribbon. But HDDs using the ATA (UDMA) 66/100/133 modes of operation require the new cables that have 80 conductors in the ribbon, 40 of which are used to shield the others from electromagnetic interference.

In fairly recent PCs, the connectors for the drives on an IDE cable are "keyed," which means that they are designed so that they can only fit into the sockets on the motherboard (or adapter card) in the correct way. If you try to plug a cable's connector in the wrong way, it won't fit.

For more information on IDE cables visit these two sections of the PC Guide site. -

Standard (40-Conductor) IDE/ATA Cables -

http://www.pcguide.com/ref/hdd/if/ide/conf_Cable.htm

Ultra DMA (80-Conductor) IDE/ATA Cables -

http://www.pcguide.com/ref/hdd/if/ide/confCable80-c.html

Visit this article on how the Cable Select (CS) feature is used to configure IDE drives - http://www.pcguide.com/ref/hdd/if/ide/conf_CS.htm.


Never open a hard disk drive

Western Digital 120GB Ultra ATA/100 7200rpm Hard Drive

Note that the Western Digital hard disk drive depicted above is shown with its top cover removed. You should never open a hard disk drive, because dust can irreparably damage or destroy it. These drives are assembled in a dust-free environment.


The safest way to upgrade RAM: Use the UK and US Crucial Memory Advisors

The memory requirements of the versions of Windows Vista

Most of the versions of Windows Vista require more RAM memory to run optimally on a computer that doesn't use memory-hungry applications than Windows XP. A video-editing application is an example of memory-intensive software. Only Windows Vista Home Basic has a recommended minimum amount of memory of 512MB, which is the same amount recommended for Windows XP. Windows Vista Home Premium, the most popular version, and Windows Vista Ultimate require a recommended minimum of 1GB (1024MB) of memory, which is twice the amount of minimum memory recommended to run Windows XP. For more information on computer memory, read the RAM pages of this site.

Paul Mullen, the highly-respected computer guru of the Helpfile at ComputerShopper.co.uk - "I have recently been buying my memory only from Crucial Technology. I would rather pay the extra cost than waste time trying to track down the obscure program faults that bad memory can cause."

UK - Crucial Memory Advisor - UK


USA - Crucial Memory Advisor - USA

For example, if your computer has an Asus motherboard, open the menu, scroll down to ASUS, and click GO. If, say, you have a Dell computer, scroll down to DELL, and do likewise. You will be taken to the relevant information on Crucial's website.

If you don't know the make and model of the motherboard installed in your computer, here is a good free utility - Belarc Advisor - that creates an analysis of the hardware and software on a personal computer. Look under FREE DOWNLOAD - http://www.belarc.com/. Another utility that also provides detailed information on the memory itself is CPU-Z.


What to look for in an IDE/SATA/SCSI hard disk drive

Here is how the specifications for some IDE/SATA/SCSI hard disk drives as they would appear in an informative advertisement.

Manufacturer
Model
Capacity
RPM
Cache
Seek Time
Interface
Maxtor
D540X
160GB
5,400
2MB
8.5 ms
ATA Ultra 100
Maxtor
DiamondMax+
80GB
7,200
2MB
8.5 ms
ATA Ultra 133

Western Digital

Caviar
120GB
7,200
2MB
8.5 ms
ATA Ultra 100
Hitachi
Deskstar 7K250
250GB
7,200
8MB
8.5 ms
ATA Ultra 133
Maxtor
DiamondMax+
300GB
5,400
2MB
12.6 ms
ATA Ultra 133
Samsung
SpinPoint SP1614C
160GB
7,200
8MB
8.9 ms
SATA 150
Seagate
Barracuda 7200.8
400GB
7,200
8MB
8.0 ms
SATA 150
Samsung
SpinPoint SP2504C
250GB
7,200
8MB
8.9 ms
SATA II 300
Hitachi
Deskstar T7K250
250GB
7,200
16MB
8.5 ms
SATA II 300
Hitachi
Deskstar 7K80
500GB
7,200
8MB
8.5 ms
SATA II 300
Hitachi
Deskstar 7K1000
1,000GB/1TB
7,200
32MB
8.5 ms
SATA II 300
Seagate
Barracuda 7200.10
750GB
7,200
8MB or 16MB
N/A ms avg
SATA or Ultra ATA/100
Seagate
Cheetah 15K.4
146GB
15,000
-
3.5 ms avg
Serial Attached SCSI (SAS)
Seagate
Cheetah 73LP
73GB
10,000
4MB
5.0 ms
SCSI Ultra 160
Hitachi
Ultrastar
146GB
10,000
8MB
4.7 ms
SCSI U320 68Pin

MB stands for megabytes, which is approximately 1000 kilobytes (KB). With regard to hard disk drives, only their data cache is measured in MB.

GB stands for gigabytes (1GB is approximately 1000MB), which is a measure of the data capacity of a hard disk drive, DVD discs, or RAM and flash memory. All current hard disk drives have their capacities measured in gigabytes.

TB stands for terabytes, which is approximately a 1000GB. The Hitachi Deskstar 7K1000, listed in the table above, has a capacity of 1TB. DVD discs currently have their capacity measured in GB. RAM and flash memory is currently measured in MB and GB.

RPM stands for the number of revolutions per minute that a magnetic platter inside a particular drive spins at.

SATA stands for serial ATA - a drive that uses a serial ATA interface, the original version of which is SATA 150. The latest version of the standard is SATA II 300.

Warranty. - You are advised to check for the warranty provided with a new HDD, as this can be for one, three, or five years, depending on the drive.

Click the name in the Manufacturer column in the above table to visit the company's website.

The 300GB DiamondMax Plus drive shown above has only 2MB of cache, a slow access time of 12.6ms, and runs at only 5,400RPM because it is designed primarily for its storage capacity for use on systems that do not require high performance accesses. Consequently, it stays cool and will probably last longer than a drive running at 7,200RPM.

Note that an SCSI drive of the same capacity as an IDE drive costs many times more than the IDE drive. In January 2003, the 73GB Seagate Cheetah SCSI drive above costs £530/$880, while the 80GB Maxtor DiamondMax+ IDE drive costs only £105/$175. An SCSI drive with a capacity of only 9GB (the Quantum Atlas V) costs £120/$200. And the 146GB Hitachi Ultrastar SCSI drive shown in the table above costs £490 in November 2003, yet a 160GB Maxtor DiamondMax Plus 9 ATA 133 drive only costs £102. Moreover, IDE ATA and serial ATA (SATA) drives with a capacity of 300GBs are now available.

SCSI drives have not reached the same high capacities as IDE drives, while the speeds of IDE drives are rapidly approaching the high data transfer speeds and access times of SCSI drives. The difference in speed is expected to be narrowed even further when serial ATA (SATA) drives reach their full potential.

In October 2003, the Raptor WD360 250GB HDD from Western Digital was the only IDE ATA drive that runs at 10,000RPM. Is it likely that more 10,000RPM IDE drives will become available in the months or years to come? - Probably not until SCSI drives run faster than that, because manufacturers like Maxtor and Hitachi would not want to ruin their own business in fast SCSI hard drives by making comparably fast ATA hard drives available.

It is now May 2006, and, so far, Western Digital is the only manufacturer of hard drives that run at 10,000RPM. The fastest IDE ATA drive currently available is the Western Digital Raptor X that spins its platters at 10,000RPM. The downside of using such a fast drive is the extra cost compared to standard 7,200RPM drives, and the extra noise they make.

March 12, 2007. - Cheap RAID Ravages WD Raptor: Is The Raptor Still The Ideal Hard Drive? - http://www.tomshardware.co.uk/...review-2111.html

In February 2003, for the price of five Ultra320 SCSI hard drives with a capacity of 147 GB, you can currently buy fifteen state-of-the-art IDE hard drives with a capacity of 200 GB.

Because SCSI drives are used in mission-critical systems, they typically still come with five-year warranties, whereas most IDE drives now only have one-year warranties instead of the three-year warranties they used to have.

It is now possible to obtain IDE drives with 8MB of cache (8192KB) compared to the previous maximum of 2MB (2048KB). SCSI drives are available with 4MB of cache. - The cache size is increasing as drive capacity is increasing remorselessly.

Note well that HDDs with a high revs-per-minute rating (7200RPM+) get much hotter than drives with a lower rating (5400RPM). Therefore, be sure to install a drive with a high rating in its bay so that it has space around it. Do not cram it in between other drives. If you have odd problems with the system, consider buying and installing a cooling unit for such a drive. If you don't require fast drive access speeds, buy a drive with a 5400RPM rating. They are less expensive, and may well last longer.

TOM'S HARDWARE GUIDE: HARD DISK CHARTS

Visit the following page to find out which hard drives are rated top dogs by THG, and compare the performance of your hard drive(s) with them.

Tom's Hardware Guide Hard Disk Charts -

http://www.tomshardware.co.uk/charts/

Articles on hard disk drives (HDDs) and solid state drives (SSDs)

Memoright SSDs: The End of Hard Drives? -

"Memoright has achieved an important milestone with its flash SSD: the device’s performance is truly better than that of any competing hard drive." -

http://www.tomshardware.co.uk/ssd-memoright,review-30808.html

WD [Western Digital] spins "world's fastest SATA hard drive" -

http://www.pcpro.co.uk/shopper/news/191529/...

Western Digital Starts Shipping 'VelociRaptor' Hard Drive For PC, Mac -

http://www.informationweek.com/news/storage/systems/...

Why Am I The Last To Know About A Dying Hard Drive? -

"Several times in the past dozen years, I've had hard drives fail. There was a horrible run of data destruction caused by three IBM Deskstar 75GXP drives before I put them all out to pasture, but several other brands have bitten the dust as well. Usually the failure was gradual enough that I could recover any recent changes on the drive and replace it. But I can't thank Windows for raising the alarm about drive failures." -

http://www.informationweek.com/blog/main/archives/2008/04/why_am_i_the_la.html

Samsung, Ridata SSDs Tested -

"It has only been a few months since flash-based solid state drives (SSDs) were launched worldwide (although Samsung’s expensive 32 GB flash drives with an UltraATA interface have been available for over a year). Unlike classic hard drives, flash-based SSDs store data onto arrays of non-volatile flash memory, while delivering good throughput with virtually nil access times and offering low power consumption. Now, Ridata and Samsung have entered the exclusive SSD market. Can they catch up with Mtron?..." -

http://www.tomshardware.co.uk/solid-state-drives,review-29818.html

Momentus 5400 FDE.2: Data Encryption On-a-Drive - Seagate Puts the Locks on Momentus Hard Drives -

http://www.tomshardware.co.uk/momentus-5400-fde,review-29806.html

'Digital locks' future questioned -

"One of the world's largest hard disk manufacturers has blocked its customers from sharing online their media files that are stored on networked drives. Western Digital says the decision to block sharing of music and audio files is an anti-piracy effort... The ban operates regardless of whether the files are copy-protected, or a user's own home-produced content..." - http://news.bbc.co.uk/1/hi/technology/7136069.stm

TravelStar 7K200 and 5K250 Beat the Band -

"250 GB notebook hard drives have been around since June of this year, when Western Digital launched its latest WD2500BEVS Scorpio drive. But others followed quickly: Samsung also has a 250 GB model, the Spinpoint M5S HM250JI, and Fujitsu has the MHY2 that we haven’t reviewed yet. The same applies to Toshiba’s 46GSX series, and Seagate is ramping up its fourth generation Momentus, the 5400.4. But for now, it is Hitachi that wants to take the 2.5" notebook drive crown. The Travelstar 7K200 is aimed at outperforming its competitors, while the 5K250 is positioned to deliver both high performance and maximum capacity..."

http://www.tomshardware.co.uk/travelstar-7k200-5k250,review-29754.html

Redefining Solid State Storage with HyperDrive 4 - HyperDrive 4 - The Fastest Hard Disk In The World? -

"SSD drives are coming, but RAM drives are the real thing for true enthusiasts. These things are super fast. We compare the new HyperOS RAM drive ..." -

http://www.tomshardware.co.uk/hyperdrive4-ssd,review-29738.html

The Terabyte Battle Continues: Enter Seagate -

"Seagate is the third hard drive maker to join the exclusive Terabyte club. How does its Barracuda 7200.11 match up to the existing giants from Hitachi and Western Digital..." -

http://www.tomshardware.co.uk/seagate-Barracuda-7200-11,review-29734.html

Parallel Processing, Part 2: RAM and HDD -

"...a RAID array has to live with a marginal performance impact due to the added controller, which results in slightly decreased performance in several benchmarks. Benchmarks that actually benefit from increased storage throughput will show the best result when going from a single drive to a RAID 0 with two drives. Running four drives still increases the storage-intensive benchmarks, but the extra gains are comparatively small..." -

http://www.tomshardware.co.uk/parallel-processing-RAM,review-29694.html

WD Caviar GP: The Green 1 TB Drive -

"Hitachi was the first hard drive maker to offer a 1 TB model, the Deskstar 7K1000, as early as the spring of 2007. Although Samsung and Seagate announced their 1 TB hard drives months ago, Samsung is past due, and Seagate’s first 7200.11 sample had to be sent back because of faulty firmware - what a pity. Thus, Hitachi has held the capacity crown for half a year, while Western Digital still holds the speed record with its 750 GB Caviar SE16. WD has now caught up with Hitachi in terms of capacity with its new Caviar GP 1 TB, which also delivers "power savings as the primary attribute" by flexibly adjusting the rotation speed between 5,400 and 7,200 RPM..." -

http://www.tomshardware.co.uk/wd-caviar-gp,review-29680.html

SAS Hard Drives: 15,000 vs. 10,000 RPM -

"The performance differences between the Savvio drives at 10,000 RPM and their 15,000 RPM brothers are substantial. The Savvio 15k.1 shows huge performance advantages in all low-level benchmarks such as the access-time measurements or the data-transfer rates. However, these benefits come at the expense of smaller maximum storage capacities (73 GB as opposed to 146 GB with 10,000 RPM) and higher costs. The 15k drives did particularly well in our I/O benchmarks." -

http://www.tomshardware.co.uk/sas-hard-drives,review-29677.html

Storage Accessories for Geeks and Pros -

"While most users’ experience with storage involves selecting internal or external PC hard drives, enthusiasts and professionals want more ..." -

http://www.tomshardware.co.uk/...review-2366.html

Understanding Hard Drive Performance: A Guide to Hard Drive Selection -

"Even experts sometimes can't tell two similar drives apart if not for their product label, but performance may vary quite a bit. Even if you compare drives with supposedly similar technical specifications, let's say hard drives within a model family, there are measurable differences..." - http://www.tomshardware.co.uk/...review-2103.html

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Five-star and four-star SATA 150/SATA II 300 and PATA hard disk drives

INTERNAL SATA AND PATA HARD DISK DRIVES

Computer Shopper gave the following internal SATA II 300 and PATA hard disk drives five or four stars in February 2008:

Click on the link to visit the manufacturer's site.

1. - Hitachi Deskstar 7K1000 HDS721075KLA330 - Five stars - Best Buy award - SATA 300 interface - 750GB (698GB formatted to NTFS file system) - Power connectors: SATA, molex - Priced at £102 in February 2008 - http://www.hitachigst.com/

2. - Samsung Spinpoint F1 HD103UI - Four stars - Most Wanted award - SATA 300 interface - 1TB (1000GB - 931GB formatted to NTFS file system) - Power connector: SATA - Expensive - Priced at £216 in February 2008 - http://www.hitachigst.com/

3. - Western Didital Caviar SE16 500GB - Five stars - Best Buy award - PATA interface 500GB (465GB formatted to NTFS file system) - Power connector: molex - Priced at £66 in February 2008 - http://www.westerndigital.com/

Computer Shopper reviewed the following internal SATA 150 hard disk drive in December 2007:

Click on the link to visit the manufacturer's site.

Western Digital Scorpio 250GB - 2.5" internal laptop PC hard disk drive - Five stars - Best Buy award - SATA 150 (SATA 1.5 Gb/s) - Rotational speed, 5,400 RPM (nominal) - Cache size, 8 MB - Priced at £90 in December 2007. - http://www.westerndigital.com/

Computer Shopper gave the following internal SATA II 300 hard disk drives five or four stars in May 2007:

Click on the link to visit the manufacturer's site.

1. - Samsung Spinpoint T166-HD501LJ - Five stars - Best Buy award - SATA II 300, 500GB, 7,200RPM, 16MB cache, 8.9ms seek time, three-year warranty, priced at £79 in November 2007 - Best Storage Product in the Computer Shopper 2007 Awards - http://www.samsung.com/

2. - Samsung Spinpoint T166-HD321KJ - Five stars - Budget Buy award - SATA II 300, 320 GB, 7,200RPM, 16MB cache, 8.9ms seek time, three-year warranty, priced at £60 in May 2007 - http://www.samsung.com/

3. - Hitachi Deskstar T7K500 400GB - Four stars - SATA II 300, 400GB, 7,200RPM, 16MB cache, 8.5ms seek time, one -year warranty, priced at £63 in May 2007 - http://www.hitachigst.com/

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Computer Shopper gave the following internal Parallel ATA IDE (PATA) hard disk drives five or four stars in May 2007:

Click on the link to visit the manufacturer's site.

1. - Samsung Spinpoint P120 (SP2514N) - Five stars - Budget Buy award - 250GB, 7,200RPM, 8MB cache, 8.9ms seek time, three-year warranty, priced at £49 in May 2007 - http://www.samsung.com/

2. - Seagate Barracuda 7200.10 Ultra ATA/100 500-GB Hard Drive - Five stars - Best Buy award - 500GB, 7,200RPM, 16MB cache, 8.9ms seek time, five -year warranty, priced at £89 in December 2007 - http://www.seagate.com/. The 320GB model (five stars) was priced at £58, and the 250GB model (four stars) was priced at £51 in May 2007.

3. - Hitachi Deskstar T7K500 - Four stars - 500GB, 7,200RPM, 8MB cache, 8.5ms seek time, one-year warranty, priced at £114 - http://www.hitachigst.com/

EXTERNAL HARD DISK DRIVES

Click here! to go to the list of external hard disk drive on Page 2 of this article. Use your browser's Back button to return to this point on this page.

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Network storage devices reviewed in Computer Shopper

Click here! to go to the reviews of network storage devices on the Networking section of this site. Use your browser's Back button to return to this point on this page.

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Visit http://www.pcpro.co.uk/shopper to read the full reviews of the following hard drives under PRODUCT REVIEWS, or enter the make and model in the site's Search For: box.

Computer hardware troubleshooting flowcharts

As you can see from looking at any of the diagnostic charts made available from the following links, there are no photo-illustrations or explanations of basic computer functions. The intended audience is the hobbyist or technician who already has some experience of repairing computers.

If you can understand a particular flowchart, it would be a good idea to print them just in case you can't boot your computer and you need the information.

Hard Disk Drive Failure: http://www.fonerbooks.com/ide_hd.htm

CD and DVD Drive Troubleshooting: http://www.fonerbooks.com/ide_cd.htm

There are other flowcharts covering the motherboard, disk drives, etc.


Round IDE hard-drive cables

You can also purchase round IDE cables. These can be used on any IDE ATA hard drive. Since they don't occupy as much space, they aid the cooling of the case, and, being easier to cover, they are more robust and hence less prone to be damaged. Single-drive cables that can accommodate a single drive instead of two drives are also available.

The image below shows the individual cables that can accommodate two IDE drives. For some reason, they come in a wide variety of garish colours, such as in blue and red.

The cables for the new Serial ATA (SATA) hard drives are so thin that it is not necessary to make them round.

Round blue IDE cables


Problems with the new round IDE cables

Anonymous post from the alt.comp.hardware.pc-homebuilt newsgroup

"Hi, I recently bought a set of CoolerMaster round IDE cables and I'm wondering if anyone has the same experience of the 45cm ones that I have. Trying to fit them on two drives close together is almost impossible without great force which didn't seem right to me. I spaced the drives apart and then only after cutting back some of the rubber shield would they bend enough to fit on the drives, if I had the drives right next to each other they just wont bend enough. The 60cm [cable] I bought for the DVD and CD burner doesn't have this problem. Also I managed to pull two of the tabs off when I needed to swap drives around. I certainly won't be buying anymore CoolerMaster cables in a hurry. I was going to buy the cheaper ones but decided on these as I thought they would be better, wish I'd have saved a few quid now."


Connecting the drives to the motherboard and the power supply unit (PSU)

Click here! to go directly to the Build a PC page on this site that deals with installing disk drives.


Serial ATA (SATA) hard disk drives

A new type of ATA hard disk drive that uses serial data transfers is now the latest type of drive. Instead of an 40-conductor and 80-conductor ribbon, or rounded IDE cable (see the section below this one for information on round cables), a serial ATA (SATA) drive's cable only has seven conductors. The image directly below shows the difference between an 80-conductor IDE ATA ribbon cable (blue) and a SATA cable (red). The considerable reduction will help with the air circulation in the computer's case.

Some optical CD/DVD drives are using Serial ATA now, so it won't be long before SATA replaces the IDE ATA standard for both hard and optical drives.

An 80-conductor IDE ATA ribbon cable and a seven-conductor  serial  ATA cable (SATA)(red) for IDE and SATA hard drives

Note that the extra 40 conductors in an 80-conductor cable (compared to its predecessor, the 40-conductor cable) are only used as protection against electromagnetic radiation that can interfere with data transfers. The 80-conductor cables have to be used with drives running in PATA 66 and higher modes of operation.

A conventional ATA IDE drive uses 40 wires for parallel transmission. The wide cable and plugs are cumbersome, and there are also a number of electrical limitations. SATA requires two pairs of high frequency cables working at a low voltage. The cables are compact and very easy to connect. Moreover, the connection limitations of parallel ATA, with its system of master and slave drives, is not longer applied to SATA drives.

SATA uses a single cable per drive. You cannot attach more than one drive to a cable. You can attach any drive to any of the SATA connection points on the motherboard. While it is no longer necessary to configure the drive using jumpers, there may be a jumper setting that can reduce the capacity of the drive for motherboards that only support a certain size of drive. The image below shows cables used to connect an SATA hard disk drive to the motherboard.

The cables used to connect an SATA hard drive to the motherboard

The installation is simplicity itself - just attach the keyed serial cable to the drive and the motherboard, and attach a power connector from the computer's power-supply unit to the drive. The cable is keyed so that one end can only connect to the motherboard and the other end to the drive, so it can't be install the wrong way round. The image below shows the connection points on a motherboard for four SATA hard drives.

The connection points for four SATA hard disk drives on a motherboard

The cables for SATA drives are usually quite stiff and the standard connectors don't have any locking facility, so they can become loose and cause intermittent connection problems, such as having Windows failing to recognise a drive.

Some hard drive manufacturers, such as Western Digital, use a proprietary SATA cable that locks to the drive. Western Digital calls its SATA cable SecureConnect. The end of the cable that connects to the drive has a special secure connector. Read the following guide to see a drawing of the cable.

Click the title to read: How To Install and Troubleshoot Serial ATA (SATA) Hard Drive.

If the motherboard has a mixture of IDE ATA and SATA drive connectors (ports), and you want to install both types of drive, consult the motherboard's manual to find out how to install a particular type of drive as the primary drive and as secondary drives.

Note that it can be tricky connecting both IDE drives and SATA drives to the motherboard. If, say, you install a SATA drive and then install an IDE drive, unless the BIOS is programed to know the difference, the system will usually try to boot from an IDE drive first. If a BIOS update isn't available that allows the two types of drive on the motherboard to be installed so that the system can boot from the SATA drive, you'll have to buy a PCI SATA adapter card and set the BIOS as instructed in this Q&A: A problem with an old IDE hard drive and a new SATA drive running from a PCI SATA adapter card.

If you are just connecting one or more SATA drives, each drive can be connected to each of the SATA connection points on the motherboard, or on a PCI SATA adapter card, because each drive has its own cable and is independently controlled by the SATA controller.

Guides on how to install SATA hard disks

Some hard-disk-drive manufacturers, such as Western Digital, use a proprietary SATA cable that locks to the drive. Western Digital calls its SATA cable SecureConnect. The end of the cable that connects to the drive has a special secure connector. Read this guide to see a drawing of the cable.

Western Digital Serial Hard Drive Installation Guide -

http://www.wdc.com/en/library/sata/2779-001006.pdf

The download is in the form of a PDF file, which requires the free Adobe Acrobat PDF reader. Here is a useful extract from it:

"Q: Why does Windows recognize the drive as "SCSI" when it is Serial ATA? A: Most third party controller cards and RAID adapters are recognized as a SCSI device under Device Manager. This is normal and will not affect your drive or system performance. Q: How do I verify if my Serial ATA drive is recognized by my system? A: Right-click on the My Computer icon, select Properties, left-click on the Hardware tab, and click on Device Manager in the window. Double-click on Disk Drives. Your new Western Digital Serial ATA drive should be listed as a "SCSI Disk Device" or "Serial ATA Disk Device." If not, make sure that all cables are securely attached and that your system BIOS has been properly configured."

The guide provides infromation on the BIOS settings, and information on how to diagnose problems, partition and format the drive, and how to transfer data from an old drive to the new SATA drive.

Note that if your PC has an elderly motherboard that only supports the original SATA standard, a SATA II drive, which has a theoretical data transfer speed of 300MB/s, will work at the slower SATA 150MB/s data transfer speed. However, to do so, some SATA II drives require a jumper on the back of the drive to be set. The jumper, which will be stored on inactive pins at the back of the drive, will have to be placed across two pins that will be indicated by a diagram on the drive. Setting the jumper makes it possible for the drive to operate at the slower speed. You can consult your PC's or its motherboard's user manual to find out if it supports SATA or SATA II. If your PC only supports SATA and you have an SATA II drive, look for a diagram on the drive that shows you how to set its SATA jumper.

You can make use of the Google search box at the top of this page (with its Web radio button selected) to conduct a search of the sites of your motherboard or SATA hard disk drive.

As with other serial standards such as USB and FireWire, SATA drives can be hotplugged and hot-unplugged. In other words, you should be able to connect and disconnect a drive while the computer is running.

However, note well that inadequate support on the part of the manufacturer of the controller, or the hard disk drive itself may make implementing this feature problematic.

As is the case with standard parallel ATA drives, PCI adapter cards for serial ATA drives (that are installed in the PCI slots on the motherboard) are available. Promise is the most well-known manufacturer of such adapter cards.

If a time comes when a standard IDE ATA controller is not available on a new motherboard and you want to use its serial ATA port for a parallel IDE drive, you can use a special adapter to connect it to the Serial ATA controller. You connect the ribbon cable to an IDE connection point on the adapter, and then connect the adapter to the motherboard with a serial ATA cable. Such an adapter, called the RocketHead 100, is manufactured by HighPoint Technologies Inc.

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Windows XP: Installing the device drivers for a boot SATA drive

SATA hard disk drives have only become available fairly recently, so Windows 98, 2000, and XP won't have the drivers for them. If you are installing an SATA drive on a system that already boots from an IDE ATA hard drive, you can obtain the driver file and point Windows to the file's location when Windows asks for it on the first boot after such a drive has been installed. But if you're installing a bare SATA drive on a new motherboard, then you have to do the following:

1. - Read the motherboard's manual, which can be downloaded from the motherboard's site if you don't have one. There will probably be a jumper that has to be enabled before the SATA controller can be used. The manual will tell you where to find the jumper on the motherboard and how to enable it.

2. - Download the SATA driver file from the motherboard's site.

3. - Copy the driver file to a floppy disk. With the SATA drive mounted in the case, connect the keyed SATA cable to the drive and the motherboard, connect a power cable from the power supply unit (PSU) to the back of the drive, and set the boot order in the BIOS to boot from CD-ROM and then SCSI. Motherboard manufacturers usually use the SCSI option in the boot order for SATA drives. The motherboard's manual will tell you what the boot order setting has to be.

Install Windows XP. Windows will detect the new drive. Press the F6 key when Windows asks you to do so, and then allow Windows to install the SATA drivers from the floppy disk. You can now install Windows, which will allow you to partition/format the drive/drive partitions as required.

Windows Vista: Installing the device drivers for a boot SATA drive

Unlike with Windows XP, which requires a floppy disk containing the SATA device drivers to be used at system startup, if the BIOS setup program recognises an SATA hard disk drive as the boot drive, Windows Vista should be able to install its device drivers during its setup installation procedure. If Vista asks for the drivers, it allows the user to search through all of a computer's storage devices for them, including a USB flash drive, not just the floppy disk drive, as is the case with Windows XP.

Installing an SATA hard drive when an IDE hard drive is installed

If you have one or more IDE hard drives installed, you should have any SATA drive you install as the boot drive, because an SATA drive is faster than an IDE drive, and, having such a thin cable, it doesn't impede the air circulation inside the PC's case. You might not be able to make an SATA drive the boot drive unless you remove the IDE drive(s). You can then install the SATA drive, install Windows or Linux and after that reinstall the IDE drive(s). You can transfer the system from an IDE drive by creating a master image of it with a program such as Norton Ghost, burn the image to a DVD, and restore it to the new SATA hard drive.

A dual-boot or multi-boot system consisting of SATA and IDE drives

The ability of a system to dual-boot or multi-boot different versions of Windows, or Windows and another operating system such as Linux that are installed on a mixture of IDE and SATA hard drives depends on the motherboard chipset and its drivers. Most recent motherboards allow booting an operating system from both channels, but in older motherboards you have to use either the SATA channel (bus) or the IDE channel, not both.

For example, with an Intel 925xe chipset from 2004, it's possible to set the device boot order in the BIOS, or choose from a boot menu which device to boot from. You can choose to boot from IDE, SATA, SATA RAID, or USB hard drives without having to switch or unplug drives. Of course, you have to be very careful when installing programs to different drives because the drive letters change. Windows rearranges the drive letters of the drives because the boot drive is the C: drive, so if one drive was the C: drive and you make another drive the boot drive, it becomes the C: drive and the other drive is given another drive letter.

Looking ahead to Intel's 925XE chipset and FSB1066 -

http://www.tomshardware.co.uk/looking-ahead-to-intel,review-1006.html

External SATA (eSATA) technology

"eSATA - Initially SATA was designed as an internal or inside-the-box interface technology, bringing improved performance and new features to internal PC or consumer storage. Creative designers quickly realized the innovative interface could reliably be expanded outside the PC, bringing the same performance and features to external storage needs instead of relying on USB or 1394 interfaces. Called external SATA or eSATA, customers can now utilize shielded cable lengths up to 2 meters outside the PC to take advantage of the benefits the SATA interface brings to storage. SATA is now out of the box as an external standard, with specifically defined cables, connectors, and signal requirements released as new standards in mid-2004. eSATA provides more performance than existing solutions and is hot pluggable." -

http://www.sata-io.org/esata.asp

SATA support in Linux

This page provides information on SATA support in Linux. You can find others by entering sata + linux + support (as is) in the Google search box at the top of this page with its Web radio button enabled.

Serial ATA (SATA) chipsets — Linux support status -

http://linuxmafia.com/faq/Hardware/sata.html

Hard disk drive problems - SATA hard drives

There are several Q&As that discuss installation and other problems to do with SATA hard drives on the Hard Disk Drive Problems pages on this site. Look on Page 1, Page 2, and Page 3.

For example, How can I restore Windows XP to a serial ATA (SATA) hard disk drive?

Here is another Q&A worth reading, because it deals with the SATA and RAID settings in the BIOS setup program:

If I connect an SATA hard drive to my PC, it won't boot. It gives error message "hal.dll is corrupted"

SATA device drivers for Windows 98 or Windows Me

This is advice I found with regard to an SATA drive in the motherboard manual for an AMD Socket 939 motherboard from MSI that runs Athlon 64 and 64 FX processors:

"MSI Reminds You... 1. Please note that users cannot install OS, either WinME or Win98, in their SATA hard drives. Under these two OSs, SATA can only be used as an ordinary storage device..."

This means that SATA drivers that can be transferred to a floppy disk, as described above for Windows XP, are not available for Windows 98 and Me. However, the boot IDE ATA hard disk drive will be able to access the SATA drive and allow files to be transferred to and from it, etc.

In short, in order to use an SATA hard drive in a PC running Windows 98 or Windows Me, the motherboard manufacturer must make the drivers for those versions of Windows available. If it doesn't you can't run those versions of Windows from an SATA drive.

If the motherboard manufacturer provides the drivers, and you are still having trouble using an SATA drive, you can find information of your own by entering a search, such as "windows 98" + sata + support (as is), in the Google box provided at the top of this page (with its Web radio button enabled).

SATA II 300

There are now two different versions of SATA. The original standard, also known as SATA I and SATA 150, supports a theoretical maximum data transfer speed of 150MB/s. SATA II, also known as SATA 300 and SATA 3GB/s, supports a maximum data transfer speed of 300MB/s.

At present, the SATA 150 standard only provides a slight increase in performance over the earlier IDE PATA standard. The full performance benefit of having SATA was supposed to arrive with new SATA II 300 hard disk drives and motherboards, which are now available (July 2005). The theoretical data transfer rate is supposed to be double the rate of the original SATA 150 standard (3GB/s compared to 1.5GB/s), and there are other technological improvements, such as intelligent data access queuing that minimises the time required to find data on the a SATA II 300 drive's disk platter.

However, the faster interface has still had little impact on drive performance, apparently because the mechanics of the drives are still not fast enough to make use of the extra bandwidth that the new standard can deliver.

Note that SATA II 300 drives can be connected to a SATA 150 connector on a motherboard, and vice versa, but a SATA II 300 drive connected to a SATA 150 socket will run at the rate of a SATA 150 drive. However, note that some SATA II 300 drives, such as those made by Samsung, have to be set manually to SATA 150 mode by using a small jumper on the back of the drive before they can be connected to a SATA 150 socket on a motherboard. Whether or not this has to be done depends on the motherboard, so check in its user manual to make sure. If you don't have a user manual for your brand-name PC or a PC's motherboard, download a copy from its manufacturer's site.

CD/DVD drives and SATA

Note that although SATA CD/DVD drives are becoming available, most CD/DVD drives still use the standard parallel IDE ATA interface. CD/DVD drives, being much slower to access, don't require a faster standard than IDE ATA, but, no doubt, they will soon be increasingly migrating over to SATA.

New-style SATA power supply units

Power connectors for SATA hard disk drives have become available on some PSUs, so no adapter cable is needed to power them. Some PSUs also even have a tachometer output for connection to the motherboard’s fan header. See the image of two SATA adapter cables below. The white plug fits into a power cable connector from the standard ATX PSU and the black plug fits into the SATA hard disk drive (or the optical SATA CD/DVD drives that are slowly becoming available).

For the time being, SATA hard drives capable of using the new power cable will also have the standard four-pin power socket. However, a conversion cable will always be available so that an old-style PSU can be used with a new serial ATA hard drive. If an older power supply unit doesn't have an SATA power connector, a converter cable can be purchased for about £4 from a vendor such as http://www.maplin.co.uk/.

SATA drive power cables that connect to the PSU (white plug) and the SATA drive (black plug)

Note that the kind of SATA connector shown above does not provide a +3.3V connection, but some new SATA hard disk drives require this voltage. If so, only one of the new ATX12V 2.0 power supply units can provide it. If you have such a drive and an old-style power supply, you will have to buy a new-style power supply. You can download the user manual for any make and model of drive from its manufacturer's site. It will provide you with the power requirements of a particular model. ATX12V 2.0 is the new power supply standard that is going to replace the ATX 1.3 standard. The 3.3V SATA connector, shown in the image below, is available in straight and angled versions, and comes directly from the ATX12V 2.0 power supply unit so that a conversion cable of the kind shown above is not used.

SATA hard disk drive power cables that come directly from a new ATX12V 2.0 power supply unit

Click here!to go to more information on the new ATX12V 2.0 PSU standard on the second of the three Motherboard pages on this site. Use your browser's Back button to return to this point on this page.

Serial ATA: a site devoted to the new IDE drive standard -

http://www.serialata.org/

Serial ATA Adapters and Cables - a US site: http://www.xoxide.com/seataad.html


Hard disk drive diagnostic and maintenance tools/utilities and tests

How to partition and format a hard drive in Windows 95/98/Me/XP/Vista

Click here! to go directly to information on Page 2 on how to partition and format a hard drive in Windows 95/98/Me/XP/Vista.

Note well that it is always sensible to make a backup of a hard disk drive that you suspect is failing (if you value its contents) before you run diagnostic tests, because the extra stress of the testing could kill the drive.

How to run CHKDSK in Windows XP and Windows Vista

In Windows XP, open My Computer, right-click on the C: drive (or any other drive you want to check), and select Properties => Tools. Click Check Now under Error-checking. A Check Disk box opens. Select the Automatically fix file system errors option and the Scan for and attempt recovery of bad sectors if you have to or want to run that very long test. Otherwise leave that box unchecked. You click the dialog box's own Start button to run the disk-check tests. A dialog box warning you that Windows can't complete the tests until you reboot enquires if you want to postpone the test until that time. It says: "The disk check could not be performed because the disk check utility [chkdsk] needs exclusive access to some Windows files on the disk. These files can be accessed only by restarting Windows. Do you want to schedule the disk check to occur the next time you restart your computer." Click the Yes option and then repeat this process for any other hard disk drives or partitions in the system. You can then reboot when all the drives/partitions have been scheduled for a disk check when Windows restarts. Windows then checks each drive or partition to whatever level of thoroughness you selected, and repairs any correctable errors.

In Windows Vista, click Start => Computer => right-click the drive that you want to check, and then in the menu that comes up click Properties => Tools => Error-checking.

Click here! to go directly to more information on chkdsk on the Recovering Windows XP page on this site. Use your browser's Back button to return here.

Read the section below to find out how to run the checks by using the chkdsk command from the command prompt.

What Windows XP's Help and Support has to say about chkdsk

"Chkdsk creates and displays a status report for the disk. The chkdsk command also lists and corrects errors on the disk. The chkdsk command with the parameters listed below is only available when you are using the Recovery Console. The chkdsk command with different parameters is available from the command prompt.

chkdsk [drive:] [/p] [/r]

Parameters

none

Used without parameters, chkdsk displays the status of the disk in the current drive.

drive:

Specifies the drive that you want chkdsk to check.

/p

Performs an exhaustive check even if the drive is not marked for chkdsk to run. This parameter does not make any changes to the drive.

/r

Locates bad sectors and recovers readable information. Implies /p.

Note The chkdsk command requires the file Autochk.exe. If it cannot find it in the startup directory (\%systemroot%\System32, by default), it will attempt to locate it on the Windows Installation CD. If you have a multiboot computer, be sure you are issuing this command from the drive containing Windows."

ScanDisk in Windows 95/98/Me

In Windows 95/98/Me, run ScanDisk (under Start => Programs => Accessories => System Tools). You have a choice of the type of test to run. Select the Thorough test if you have problems with the drive that the Standard test doesn't fix with the Automatically fix errors box checked. The Thorough option can take a half an hour or more to run, depending on the size of the drive or partition. Windows should complete the tests without the need to reboot. Repeat this process for any other hard disk drives or partitions. If you can't run the Thorough tests from Windows, you can run the same tests from MS DOS in Windows 98. Restart the computer , press the F8 key after the system beep, and run the Command Prompt Only option. At the C:\> prompt enter the command ScanDisk /all /autofix /surface to to run the Thorough check and repair all the drives in the system. Omitting the /surface switch in the command runs a faster but less thorough check.


Third-party hard drive diagnostic utilities and tools

MHDD is the most popular freeware program for low-level hard-disk-drive diagnostics. -

http://hddguru.com/content/en/software/2005.10.02-MHDD/

You can find many other free hard-disk-drive utilities at http://hddguru.com/.

Diagnostic utilities provided by hard disk drive manufacturers

Most of the HDD manufacturers (Seagate, Maxtor, Western Digital, etc.) provide a diagnostic utility that can be used to diagnose problems with their drives from their websites. These utilities might also be able to partition and format a hard disk drive, which is a godsend if you're using Windows 95/98/Me with a drive(s) larger than 64GB, because the DOS FDISK utility has problems with drives of that size and larger - even if you're using the updated version. Click here! to read more about FDISK on this page. Use your browser's Back button to return here.

Where to download the hard-disk-drive diagnostic utilities for a particular make of hard drive

Seagate - SeaTools: http://www.seagate.com/www/en-us/support/downloads/seatools

Note that Maxtor and Quantum drives use SeaTools (above).

Western Digital - Data Lifeguard: http://support.wdc.com/download/

Samsung - Choose Hutil or Shdiag:

Hutil - http://www.samsung.com/global/business/hdd/support/utilities/Support_HUTIL.html

Shdiag - DOS utility - http://www.samsung.com/global/business/hdd/support/utilities/Support_Shd