External Hard Disk Drives

External USB/FireWire/eSATA hard disk drives

The image above depicts the back of a Maxtor OneTouch 250 GB external hard disk drive, suitable for use with a desktop PC, showing its ports. The image shows a close-up of the rear view. The USB 2.0 port is on the left followed by two FireWire ports (FireWire 400 and FireWire 800), which means that it can be connected to a PC or an Apple Mac. Beside them is the power connection and the on/off switch. Mouldings that can interlock allow several OneTouch drives to be stacked one upon another. The OneTouch drives also come with a stand that allows them to be positioned vertically on a desktop.

Note that USB 3.0 external hard drives are now available. USB 3.0, also known as SuperSpeed USB, has a maximum data transfer speed ten times faster than that of USB 2.0. USB 2.0 external drives are still available, so, given that external drives are used mainly for data storage, why buy one when you can get a superior USB 3. drive? Note that although USB 3.0 has the potential to be ten times faster than USB 2.0, the best USB 3.0 external hard drives are currently only up to four times faster than USB 2.0 models, because theoretical data transfer speeds are never attained in practice.

An eSATA connection is probably just slightly slower than USB 3.0, but not many desktop and even fewer laptop motherboards provide an eSATA port. The cheapest way to add eSATA to a desktop PC is to buy an eSATA bracket, which is connected to an SATA port on the motherboard, which provides the external port. Adapter cards are also available that can add eSATA connectivity, but it is not worth the extra expense involved given that most new desktop and laptop PC now provide USB 3.0 connectivity, albeit you will probably have to install the driver from the driver disc that came with the computer or USB 3.0 adapter, because only Windows 8 supports it natively, which means that earlier versions of Windows require the driver to be installed instead of Windows recognising the device and installing it automatically. Moreover, the maximum cable length of USB 3.0 exceeds that of eSATA. Note that an external eSATA drive requires an external source of power, whereas a USB drive is powered via the USB cable. Therefore, USB 3.0 is the most convenient of the two connections, especially when using Windows 8 devices. Windows 8 is to be made available officially in the fourth quarter of 2012. For more information, use the web-search query: usb 3.0 vs esata.

Note that Intel's Thunderbolt interface is gaining ground due to having the potential to be twice as fast as USB 3.0. It is currently only found on Apple Macs and some Intel desktop-PC motherboards.

Thunderbolt (interface) -

http://en.wikipedia.org/wiki/Thunderbolt_%28interface%29

Many users are reporting external hard drives dying on them for no reason on the web. Their solution is to buy a HDD docking station for standard 2.5-inch and 3.5-inch SATA hard drives that allows them to be used as external drives that are no more likely to die than the standard hard drives that are used, which is not very likely. The following webpage shows how they work.

http://www.ineotechusa.com/product-na317u+_t3527.html

A good buy is the Icy Box USB 3.0 docking station that currently costs only £19.99 from Amazon.

http://www.amazon.co.uk/Icybox-USB-Dockingstation-inch-SATA/dp/B0091C8TFQ/....

External drive manufacturers are experimenting with SSD drives, because the combination of the two technologies will provide the fastest data transfers. The downside is that SSD drives using Thunderbolt are currently very expensive compared to USB 3.0 drives.

If you run a business and you want a waterproof and fireproof external hard disk drive to give a high level of physical protection to your data, they can be bought fairly inexpensively. For example, (in July 2012) the ioSafe Solo 1TB model was priced at only £150 with the 2TB model costing £190. Visit iosafe.com for more information. Rugged portable external drives are also available from that manufacturer.

In September 2012, Western Digital announced the release of what it calls its smallest USB 3.0 external hard disk drive for PCs and Apple Macs - the 500GB My Passport Edge. Searching the web for usb 3.0 external hard drives provides plenty of information, reviews, manufacturers and vendors.

External SSD drives that use the SATA data-transfer standard and external drives with USB 3.0 (USB SuperSpeed) connectivity are available. Being purely electronic devices, they won't be damaged by rough treatment, dropping, etc., and therefore make better portable drives. Standard disk-based external drives are mechanical devices with read heads and spinning platters and are therefore easily damaged or destroyed by being dropped. External hard drives with a huge 3TB capacity are currently available and this will keep increasing, but external SSD drives are small and very expensive by comparison. For example, in July 2012, an Iomega 35143 256GB SuperSpeed USB 3.0 2.5 Inch External SSD Flash Drive could be bought for around £480.00, with the cheapest 128GB external drive costing around £120.00. 128GB of data storage doesn't go very far these days.

If protecting your data against theft is your main consideration, external hard disk drives that require a PIN to be entered on the drive's own keypad before the data can be accessed are available from istorage-uk.com and originstorage.com. Origin Storage external hard drives are encrypted using 256-bit AES encryption, the level used by the US military.

Note that to be used as boot drives that start the system hard drives with a capacity exceeding 2.19GB require an EFI BIOS. Windows Vista and Windows 7 fully support storage (non-boot) drives larger than 2.19TB. For example, Windows Disk Management can format a 3TB external drive normally as long as the user chooses to format the drive as a GPT partition, which allows Windows Vista/Win7 to create a single partition of a drive with a capacity exceeding 2TB. Windows XP cannot format drives exceeding 2.19TB, but if the drive is an external, non-boot drive, the drive manufacturer provide and installation option to format it for Windows XP compatibility. The drive's user manual should explain what to do.

Read the following Q&A on this website for more information on this topic: Can an ultra-large-capacity 3.0TB hard disk drive be used with Windows XP, Vista or Windows 7?

A portable USB external drive - one specifically designed to be used away from mains power - should be able to work when attached to a USB cable attached to a laptop computer. However, if the USB cable can't provide enough power, buy a USB Y cable that provides two USB "A" male connectors that power the drive and a single USB "mini-B" male connector that is used for data transfers. The "mini-B" male connector connects to the drive itself and the two USB "A" male connectors connect to the laptop.

A USB 2.0 device can draw up to 500mA of power, which is insufficient to power some external drives, which means having to use a Y cable. The USB 3.0 standard increased that limit to 900mA, which should be enough to power most external drives.

There has been a recent update to the USB specification called the Battery Charging Specification, which allows 1.5A to be drawn from a single USB port, released in March 2007 and updated in 15 Apr 2009. This is intended for USB chargers, but some laptop computers provide a Charging Downstream Port, which supports it. There is not much information available on the web on this topic, only a bit on this page: http://en.wikipedia.org/wiki/USB

eSATA (external SATA) external hard drives are also available. The eSATA interface is slightly slower than USB 3.0, but most laptops and many desktop PCs don't provide eSATA ports. Fortunately, cheap external brackets (backing plates) that connect to an internal SATA header on a desktop-PC motherboard and adapter cards are available for both desktop and laptop PCs. To add eSATA support all you have to do is buy the correct external bracket or adapter card. An adapter card will be either a PCI or PCI Express card for a desktop PC and a CardBus (old standard) or ExpressCard (latest standard) for a laptop.

You must make sure that your desktop PC's motherboard has a free slot for the type of card that you intend to purchase and that your laptop has a CardBus or ExpressCard slot. The short PCI Express cards can all be installed in the longer PCI Express slots. E.G., an x1 card can be installed in a x4, x8 or x16 slot; an x8 card can be installed in an x16 slot, etc. Most new laptops only have an ExpressCard slot and CardBus adapters are becoming increasingly difficult to buy new.

Using a high-capacity external hard drive is the most convenient and reliable way of storing backups and system images for the home user. You can back that method up by making use of an off-site online service to store data files or even the full backups themselves. This page on this website deals with the ways of creating and restoring backups.

A desktop external hard drive with a capacity of 1TB (1024GB) currently (Sept. 2011) costs about £50. 4TB internal hard drives are available. The capacities are increasing all the time. A 2.5-inch portable external drive is the best choice if you have to access files while on the move via a laptop PC. They are currently available in capacities up to 1TB. 1.8-inch iPod-sized external drives with capacities up to 250GB that can fit in a coat pocket are also available if portability is particularly problematic. If you need quick data transfer speeds a drive with a spindle speed of 7,200 rpm (revs per minute) is best. Most 2.5-inch and 1.8-inch drives have a spindle speed of 5,400 rpm. The faster the rpm, the faster the data is transferred. Most desktop PC internal hard drives now have a spindle speed of 10,000 rpm.

An external hard disk drive is an external device that may contain data that you would like to protect. There are two main ways of protecting the data on one - by making use of encryption software that can also provide password protection, which can be free or paid for, and by making use of a password-protected screensaver that you can activate when you are not at the computer. Some external hard disk drives come with encryption software that also provides password protection. Note that the free encryption software tends to be difficult to use while the paid-for software is much easier to use but worth the price if you don't want to read through a user manual.

Encryption of a whole drive or just some of the data on it will only provide security when the external drive is not connected to the computer that encrypted that data. Anyone trying to connect the drive to another computer or to your own computer will not be able to access the data because it is both encrypted and password-protected. But when the drive is connected to its computer, anyone will be able to access the data, so the best way to protect it is to make use of a screensaver that provides password protection that can be activated when you are away from the computer or after a set period of the computer being inactive. If you don't know anything about screensavers, enter the word screensaver in the Search box of Help and Support in Windows XP, Windows Vista and Windows 7. Here is a thread from a computer forum that deals with this subject:

How to password-protect an external hard drive -

http://windowssecrets.com/forums/showthread.php/...

Remember that USB 3.0 is now available. It is much faster than its predecessor, USB 2.0. The best USB 3.0 external hard drives are up to four times faster than USB 2.0 models. Visit the USB section of this website for more information on the new USB standard, which can be added to a desktop or laptop computer without it in the same ways as USB 2.0 can be added. The first USB 3.0 external hard drives were made available in October 2009, but most existing desktop and laptop PCs don't have USB 3.0 ports and you have to make sure that USB 3.0 is a specification of a new computer, because the new standard's adoption is taking place slowly. PCI and PCI Express USB host controller adapter cards for desktop PCs that fit into a PCI or PCI Express adapter slot on the motherboard are available that add USB 3.0 ports. Note that the PCI and PCI Express standards are not interchangeable. A PCI card has to be installed in a PCI slot on the motherboard. The same applies to a PCI Express card. PC Card USB 3.0 host controllers for laptop computers are also available.

USB 3.0 increases data transfer speeds hugely compared to USB 2.0, so there is not much point in buying a USB 2.0 external hard drive. The most expensive way to add USB 3.0 to a desktop PC is to replace the motherboard with one that provides it, which you would only do if you also wanted to upgrade the processor and RAM memory. PCI Express x1 adapter cards start at only £15 and since x1 is smallest size, such a card can fit into any free PCI Express motherboard slot. CardBus adapter cards with USB 3.0 for a laptop PC are not available, but ExpressCard adapters starting from £25 are. However, they protrude from the computer, so have to be removed when on the move.

Buffalo ships world's first USB 3.0 hard disk drives this month [October 2009] -

http://www.engadget.com/2009/10/07/...

Three External (and Fast) USB 3.0 [Hard Disk] Drives Compared -

"The first USB 3.0-based external hard drives aim at eliminating the USB 2.0 bottleneck (that hovered around 30 MB/s) with enough bandwidth to outperform the fastest mechanical disks. A-Data, Buffalo, and WD do battle for maximum performance." -

http://www.tomshardware.co.uk/usb-3.0-superspeed-external-drive,review-31952.html

There are three current interfaces that can be used to connect external hard disk drives - USB, FireWire and eSATA (dealt with on this page).

USB 2.0, FireWire, Or eSATA: Which Interface Should You Use? : USB/FireWire/eSATA: 2.5" And 3.5" Storage Options -

"Adding external storage to your PC can be a mess if you aren't familiar with the various interfaces in play. Should you go for compatibility with USB 2.0 or is FireWire a better choice? What about eSATA, which matches native hard drive performance?"

Note that USB 3.0 is now the latest USB standard, which is up to four times faster than USB 2.0 in practice; ten times faster in theory. -

http://www.tomshardware.co.uk/usb-firewire-esata,review-31793.html

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There are two main types of external hard disk drives: models designed to be used on a desk and those designed to be portable.

External hard drives come in all kinds of shapes and sizes - tower units, horizontal desktop units, and portable units.

Note that most portable and desktop external hard disk drives come with bundled backup software.

Desktop external hard disk drives have the highest capacities of the two types, and therefore also the lowest cost per gigabyte (GB). They require an external power supply, which is not a problem for desktop use.

Desktop units with 1 terabyte - 1TB (1000MB) - of storage space are now common. (Remember that the hard-drive manufacturers use 1,000KB = 1MB and 1,000MB = 1TB, whereas the true mathematical figures - 1,024KB = 1MB and 1024MB = 1TB - are used by software developers (Microsoft, etc.). Therefore, a hard drive always has more disk space according to the manufacturers than is reported by Windows XP/Vista/7.

You should use a portable drive if you want to carry it with you with a laptop PC or transfer files from one computer to another. Portable drives are based on laptop hard drives. They don't require an external power adapter, are smaller and lighter, less spacious , but more expensive than desktop drives. However, some portable drives have to be connected to two USB ports via a special cable in order to be able to draw sufficient power.

It's possible to purchase external hard disk drives (HDDs) that connect to a computer via the Serial ATA (SATA), eSATA, USB or FireWire interfaces. More information on the external form of SATA called eSATA is provided further down this page. The SATA interface is more commonly used to connect internal hard disk drives, but a growing number of PC motherboards now provide an external SATA (eSATA) port.

Most external hard disk drives use a USB 2.0 (USB Hi-Speed) interface. All new and fairly recent computers have external USB 2.0 ports. The theoretical maximum rate of data transfer is 60MB/s (megabytes per second), which, as is usual with these standards, is never reached in practice.

There are two versions of the FireWire interface - FireWire 400 (50MB/s) and FireWire 800 (95MB/s). A FireWire 400 connection is usually faster than a USB 2.0 (USB High Speed) connection, but, along with eSATA, the fastest of all is the new USB 3.0 (SuperSpeed USB), which is theoretically ten times faster than USB 2.0, but only four times as fast in practice. Therefore, if you transfer very large files or large numbers of files, a USB 3.0 connection is by far and away the easiest and fastest to use.

A FireWire 800 connection is faster than USB 2.0, but very few external hard drives or computers provide a FireWire 800 port. An example of an external drive that provides a FireWire port is the Lacie Little Big Disk Quadra (eSATA 3Gbits, FireWire 800, FireWire 400, USB 2.0) drive that can be powered via the FireWire cable or by an external power supply.

All external hard drives, which are mainly used for backups, now use USB 3.0 because of the great increase in speed compared to USB 2.0. I have yet to see a current external hard drive that provides a FireWire port.

A PCI adapter card that adds FireWire 800 support to a PC can be purchased for around £30. Note that FireWire PCI Express adapter cards are now available, such as the Belkin FireWire 3-Port PCI Express Card.

Just as there is little performance increase between SATA I 150 and SATA II 300 hard drives, it doesn't make much difference if a FireWire 400 or FireWire 800 port is used because of the speed limitations imposed by the mechanical nature of hard drives. The platters can only revolve and the data can only be picked up and transferred across cables at a maximum rate that can't be exceeded just by using an interface that provides bandwidth that exceeds those mechanical limitations. You can design a motorway so that it has a speed limit of 700MPH, but there is no point in doing that if the cars themselves can't exceed 250MPH.

The SATA 150 interface transfers data at a theoretical maximum rate of 150MB/s, but an external SATA hard disk drive can't get anywhere near that maximum rate.

Make sure that you purchase an external drive with an interface that your computer supports. If you have an elderly computer that only has USB 1.1 ports, you have to buy a PCI adapter card that has USB 2.0 or FireWire 400/800 ports. It is usually installed in a PCI slot on the PC's motherboard. (At the time of writing in August 2008 there were no USB 2.0 PCI Express adapter cards, but FireWire PCI Express adapter cards were available, such as the Belkin FireWire 3-Port PCI Express Card.)

All ATX motherboards have had the PCI 2.x or PCI-X slots that accommodate the current PCI adapter cards for many years. If you buy a PCI Express adapter card for a desktop PC, you must make sure that you have the type of free PCI Express slot on the PC's motherboard that the card uses. PCI Express slots come in three sizes - x16, x8, and x1. The motherboard's user manual will tell you which slots it has. The motherboard manufacturer's website provides manuals in the PDF format.

eSATA (external SATA) external hard drives are the fastest of all, but unless you have a very recent desktop or laptop PC, you will have to add eSATA ports by using a PCI expansion card ( for a desktop PC), or an ExpressCard or CardBus expansion card (for a laptop PC). (eSATA PCI Express adapter cards are also available for desktop PCs that have the required free PCI Express slot on the motherboard.) You can make use of a search engine to locate information and vendors for them. If you need an eSATA CardBus card for a laptop PC, for example, you could try using a search query such as: esata cardbus.

Due to the current fast interfaces (USB and FireWire), external hard disk drives are no longer as slow as they used to be in comparison to internal IDE/SATA and SCSI hard disk drives. However, internal hard disk drives still perform about twice as fast as external ones, particularly when very large files, such as digital video files, are being accessed or transferred.

It is also possible to use an ordinary IDE hard disk drive as an external drive by installing it in a special enclosure that uses a USB or FireWire port. See the Q&A on this site called: How to make an ordinary internal IDE hard disk drive into an external drive.

External Hard Drive Charts - "This page is updated on a regular basis and provides a unique resource for everybody who is looking for a desktop [external to the PC] hard drive - whether it is for home or for business use." -

http://www.tomshardware.co.uk/charts/external-hard-drive-charts/...

External Storage: Terabyte [1,000MB] Drives Compared : Value-Added External Terabyte Storage -

http://www.tomshardware.co.uk/-external-hard-drive,review-31383.html

External hard disk drives can easily be used as removable system back-up devices, or to transfer data between non-networked computers.

Like most speaker systems, the large 3.5 inch external hard disk drives - whether USB or FireWire - require more power than they can draw via their connection to the computer, so they are supplied with an external power supply unit. Therefore they are usually more expensive than internal hard disk drives, which take their power directly from the computer's power supply unit. However, the smaller 2.5 inch drives are able to draw their power from the system via their USB or FireWire connection, do not require an external power supply unit, and are therefore cheaper than the larger external drives, but are still more expensive than equivalent internal drives because of their special casing.

i.Link is the Sony version of FireWire, which is technically identical to it but uses an external mains power supply instead of taking power through the computer, thereby making it an excellent choice for a notebook owner who doesn't want to run the portable computer's battery down by using a power-hungry external device.

External 2.5 or 3.5 inch hard disk drives are really just internal drives placed into an external case and provided with a USB 1.1, USB 2.0, or FireWire interface. Read and write speeds are adversely affected by the necessity for the extra interface compared to drives using the internal motherboard's IDE interface.

USB 2.0 external drives are backward compatible with the USB 1.1 standard, so a USB 2.0 drive will work on a USB 1.1 connection at the USB 1.1 transfer speed, which, you should note, is much slower than a USB 2.0 connection. USB 3.0 is also backward compatible with USB 2.0, but not with USB 1.1. Connecting a USB 3.0 device to a USB 2.0 port will make it function at USB 2.0 connectivity speeds.

If your computer doesn't have a motherboard that supports USB 2.0/3.0 or FireWire, you can obtain a PCI or PCI Express add-on adapter card for about £20/$30.

Because USB and FireWire devices can be connected to a computer while it is switched on (hotplugged), besides being useful for creating back-ups that can be stored off-site, external hard drives are very handy for transferring data between computers that are not networked. Windows should detect the connection and load the drivers for the drive automatically.

Click here! to find out how to partition/activate and format a new external hard drive in a Windows 95/98/Me and a Windows XP/Vista/7 system on this page. Use your browser's Back button to return to this point on the page.

External hard disk drives can usually be obtained from the same vendors that sell the internal drives, but some manufacturers specialise in external drives.

The main manufacturers of external hard disk drives are:

Seagate - http://www.seagate.com/

Western Digital - http://www.westerndigital.com/

Buffalo - http://www.buffalo-technology.com/

LaCie - http://www.lacie.com/

EZQuest - http://ezquest.net/ezq/index.php

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Computer storage devices rated and reviewed by Expert Reviews

Expert Reviews - storage reviews - http://www.expertreviews.co.uk/storage

The above page on the Expert Reviews website provides reviews on the following storage devices:

• Internal hard disk drives
• External hard disk drives
• DVD/Blu-ray drives
• Network attached storage (NAS) devices
• USB flash drives

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External SATA (eSATA) hard disk drives

eSATA is part of the SATA standard, but it isn't just internal SATA extended into an external enclosure. The eSata standard is a standard of its own that defines the interconnect (the design of the connectors) - the signalling requirements and user features such as shielded cables and hot-plug connections. The connector for an eSATA cable is different from a standard SATA 150 or SATA 300 cable, so you can't use a standard motherboard SATA cable.

External SATA or eSATA is supported by many makes/models of ATX desktop PC motherboards, which provide an eSATA port on the ports panel. If a motherboard doesn't provide an external eSATA connector, some motherboards provide an option (often as an optional extra) to install eSATA ports in the form of a cabled bracket containing them that fits into an expansion slot at the back of the case. The cable is connected to an SATA header on the motherboard.

If neither of those options are available, PCI/PCI-X and PCI Express eSata controller cards are available that you install in a PCI slot (which all motherboards have had for may years), or in a PCI Express slot. The controller is usually installed in a PCI Express x1 slot. Most recent motherboards provide at least x1 slot. Your PC's motherboard's user manual will tell you which ports it provides for adapter cards. If you don't have a manual, the motherboard's manufacture provides them in the PDF format. You can use the free CPU-Z utility from cpuid.com to identify the PC's motherboard (make/model).

You can locate vendors for the above-mentioned controller cards by entering a search term such as esata controller card in a search engine.

eSATA is currently the best option to use for an external hard drive, because it is actually (not just theoretically) much faster than USB 2.0 (USB Hi-Speed), USB 3.0 (SuperSpeed USB) and FireWire 400 or 800. USB 3.0 is up to four times faster in practice than USB 2.0, but an eSATA connection is slightly faster.

Seagate 500 GB External Hard Drive Goes eSATA : 500 GB -

http://www.tomshardware.com/reviews/....

eSATA External Hard Drive [PDF document] -

"An eSATA PCI host adapter card is included with your Seagate eSATA drive in order to provide the necessary connection between your computer and the drive. Before using the drive, please install the PCI card by following the instructions in the enclosed Quick Install Guide." - http://www.seagate.com/docs/pdf/datasheet/disc/ds_ext_esata.pdf

Theoretical and actual bandwidths

Interface	Theoretical bandwidth	Bandwidth achieved in practice
USB 1.1 (old)	12 MBit/s [1.5MB/s]	1 MB/s
USB 2.0	480 MBit/s [60MB/s]	25 MB/s
FireWire 400 (IEEE 1394A) / i.Link	400 MBit/s [50MB/s]	30 MB/s
FireWire 800 (IEEE 1394B) / i.Link	800 MBit/s [100MB/s]	60 MB/s
Serial ATA - SATA I 150	1500 MBit/s [1.5 GBit/s or 150MB/s]	118 MB/s
Serial ATA - SATA II 300	3000 MBit/s [3.0 GBit/s or 300MB/s]	118 MB/s

eSATA has the same figures for SATA 150 or SATA 300, depending on the version of SATA being used by the motherboard.

Click here! to view the theoretical bandwidth (not the bandwidth achieved in practice) of all of the computer storage standards. The page contains the bandwidths of all of the other computer standards, such as PCI, AGP, PCI Express, etc.

The bandwidth of each of the interfaces, which is a theoretical or actual measure of the data transfer speeds of an interface, is shown in megabits per second (MBit/s), and megabytes per second (MB/s). There are eight bits in a byte, so dividing MBits/s by eight converts it to MB/s.

Note that data transfer rates are limited by mechanical hard drives themselves, not by the interfaces. The fastest modern desktop hard drives transfer data at a maximum of about 118MB/s, which is well within the capabilities of even the older IDE ATA/133 specification. An analogy would be a highway that allows speeds of 700MPH, but cars that can only reach a maximum speed of 270MPH.

All of the facts and figures of SATA and eSATA are provided here:

Serial ATA - http://en.wikipedia.org/wiki/Serial_ATA

USB 2.0 and the new SuperSpeed USB (USB 3.0), which are backward-compatible with each other, are the most common standard used for external hard drives. Have a look at this page to see which standards are supported by the models of external hard drives made by Lacie:

http://www.lacie.com/products/range.htm?id=10033

If that link doesn't work, visit lacie.com to access the products.

External IDE hard disk drive enclosures with USB, FireWire, eSATA ports

External enclosures for standard IDE ATA and SATA hard disk drives that provide them with USB 2.0, eSATA, and FireWire ports are available. So, if you have any old IDE (PATA) hard drives taken from a PC that you have upgraded, etc., you can make use of it as an external backup drive. Note that you probably won't be able to find an enclosure with all three types of ports.

The image below shows the back view of an enclosure that accepts an IDE or and SATA hard drive and can be connected to either its USB 2.0 or eSATA port.

An old or new 3.5" IDE or SATA hard disk drive can be installed in such an enclosure so that it can be used as an external drive via a USB, FireWire, and eSATA ports, depending on which types of ports the enclosure provides. The enclosure shown above does not provide a FireWire port, but other makes/models do. The installation of the IDE or SATA drive in the enclosure is a simple matter. No technical expertise is required.

Everything necessary except the hard disk drive itself is included in the package - the installation instructions, a 6-6-pin FireWire cable, USB cable, eSATA cable, power supply, fitting screws, etc.

The enclosed IDE/SATA drive can then be used for any number of purposes, from backing up to storing video, image, and music files. It can also be shared between computers, using it as a data pool. If it has both USB and FireWire interfaces it can be used on almost any PC or Apple Mac.

Using an ATA IDE (PATA) or SATA drive in this way is a much cheaper alternative to buying an external (USB, FireWire, eSATA) hard drive.

Enclosures that accept only SATA hard drives are already the dominant type. Soon, the manufacturers won't be manufacturing enclosures that accept IDE drives, because there will be little demand for them as that standard dies out.

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USB-to-IDE and USB-to-SATA converters cables/adapters

You can buy a USB-to-IDE or a USB-to-SATA converter that allows you to connect an IDE or SATA hard drive or CD/DVD optical drive to a USB port. You can also buy a single converter that can be used with both IDE and SATA drives. If necessary you could probably connect it to USB header on the computer's motherboard so that you can install the drive in a bay in the PC's case instead of as an external drive. You can use it for doing malware scanning from a known uninfected PC on the drives of other PCs, transfer files from an old PC's hard drive to a new PC's hard drive, etc.

To locate vendors, you can enter a search term such as usb + ide + sata + converter (as is) in a search engine.

Here is an example I found:

Bipra USB 2.0 to SATA/IDE Adapter Kit with Power Adapter for 2.5/3.5/5.25 Inch SATA or IDE Drive -

Allows any SATA or IDE drive to be connected to a computer's USB port. Read the numerous purchasers' reviews.

http://www.amazon.co.uk/Bipra-SATA-Adapter-Power-Drive/...

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How to configuring and install a hard disk drive

The method of configuration and installation depends on the type of hard drive being installed. The methods differ for the three main types - IDE ATA, SATA, and SCSI. IDE ATA hard drives are still manufactured, but are in the process of being replaced by SATA hard drives in home PCs.

There is usually a diagram on an IDE ATA hard drive itself (of the kind illustrated in the image below), showing the jumper settings to configure it as a master or slave device. The configuration table is fixed to the top or bottom of the drive.

The Master, Slave, and CS Enabled (Cable Select) jumper settings are clearly shown on the Maxtor drive shown above.

Note that due to political correctness that is offended by the words Master and Slave, new drives will probably be using the terms Primary and Secondary instead, but I will continue using the clearer Master and Slave. A PC with four drives would have a primary master, a primary slave, a secondary master, and a secondary slave, but if Primary and Secondary replace the traditional terminology, the four drives will be called a primary primary, a primary secondary, a secondary primary, and a secondary secondary, which is somewhat absurd.

The Cap Limit setting shown in the image above automatically sets the drive to a system's maximum size capacity, because many systems cannot run huge drives. This particular DiamondMax Plus drive (5400RPM, 2MB cache, 12.6ms disk access time), has a capacity of 300GB that unmodified Windows 9x systems, which run the FAT16 or FAT32 file systems, won't be able to run as a single (unpartitioned) volume. Windows XP/Windows Vista, running its NTFS file system, can run such a drive unpartitioned if the motherboard's BIOS setup program allows it. Windows XP was released in October 2001. Nevertheless, you need to install Service Pack 1 (SP1) or Service Pack 2 (SP2), which incorporates it, to be able to use drives larger than 137GB. Needless to say, Windows Vista supports drives larger than 137GB.

For more information on what you need to know in order to upgrade a hard drive on a particular PC, visit this Upgrade Checklist on this website.

If the BIOS doesn't allow it, reflashing it with the latest BIOS file from the PC manufacturer or motherboard manufacturer's site might fix the problem. Otherwise, installing a new PCI IDE adapter card of the kind made by Promise (site: promise.com), or a new motherboard that has a BIOS capable to recognising such a large hard drive is the only remedy.

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) and on the drives themselves in the correct way. If you try to plug a cable's connector in the wrong way, it won't fit. A different system was used before the connectors were keyed. The page provided at the end of this section provides details of both types of connection.

I prefer using the sound Master/Slave settings to configure drives, but the easiest way to configure and install an IDE ATA 66/100/133 HDD, which has to be installed using an 80-conductor ribbon cable (not an old-style 40-conductor cable), is to set the drive's jumpers to the Cable Select setting. When jumpered for Cable Select, the cable plus the jumpering determines which is the master drive and which is the slave drive. The master drive will go to the black connector on the 80-conductor ribbon cable, and if a slave is used, it will be connected at the ribbon's middle (grey) connector. The ribbon's blue connector fits to the motherboard.

As long as two hard drives on the same cable are jumpered to the Cable Select setting, you can swap them from the master to slave positions on the ribbon cable. But, if you swap a drive set as Master to the position on the cable for a Slave drive, you have to change the jumper setting to Slave or the drive won't be recognised by the system.

This page - How to Build a PC - Page 3 (a set of six pages on this site) - contains information on how to configure and install IDE ATA and SATA hard disk drives. It also includes information on installing CD/DVD and floppy disk drives.

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.

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Partition and format a hard disk drive in a Windows 95/98/Me system, or by using the Disk Management feature in Windows XP/Windows Vista/Windows 7

Read Partition Planning here - http://aumha.org/a/parts.htm - if you want advice on choosing a partitioning strategy that best suits your computing needs.

Windows 95/98/Me

Note well: back the system up, or implement whatever your back-up routine is before you attempt to partition of format a hard disk drive. Because if the process goes awry for any reason, such as a power failure, you might have to reinstall Windows, which would mean a loss of data if no back-up is available to be restored.

In a MS DOS/Windows 95/98/Me system, you would use the FDISK utility to partition a hard disk drive, and the DOS format [drive letter followed by a colon (C:)] command to format a whole drive or a partition on a drive. (Enter the word command in the Start => Run box to bring up a DOS window within Windows, and enter format /? to bring up the information on the format command.)

Click here! to go to some very useful information on FDISK on this page. Use your browser's Back button to return here.

Unless you use a Windows program such as Partition Magic, you can only partition the drive from full MS DOS mode (not MS DOS running within Windows), but you can format the non-boot partitions from My Computer (on the Windows Desktop or in Windows Explorer) by right-clicking on the the drive's graphical entry and then clicking on Format.

In an emergency, you can access partition information and format the boot partition (usually the C: drive) containing Windows (or any other partition) of a Windows 95/98/Me system from a start-up floppy disk by using the usual DOS format and FDISK commands.

Windows XP

When you first install Windows XP on a computer from its installation CD, the system has to boot from the CD, which means that the CD/DVD drive must be set as the first boot device in the PC's BIOS. An unpartitioned and unformatted hard disk drive will have to be partitioned and formatted from the Windows CD before Windows can run its setup routine.

To partition and format a new hard disk drive (which could also be an external hard disk drive using an eSATA, FireWire or a USB connection) from within Windows XP, click Start => Control Panel => Performance and Maintenance => Administrative Tools => Computer Management. From the list in the left pane, click Storage to expand the list, and then click Disk Management.

Or just enter diskmgmt.msc in the Start => Run box.

You can also use the command prompt (command line).

MS Knowledge Base articles on configuring hard disk drives:

1. - How to use Disk Management to configure basic disks in Windows XP -

http://support.microsoft.com/kb/309000

2. - How To Use Disk Management to Configure Dynamic [Hard] Disks in Windows XP - This step-by-step article describes how to use the Disk Management snap-in to configure dynamic [hard] disks. - http://support.microsoft.com/?kbid=308424

The following page provides information on the difference between basic disks and dynamic disks.

Logical Disk Manager - http://en.wikipedia.org/wiki/Logical_Disk_Manager

3. - How to enable 48-bit Logical Block Addressing support for ATAPI disk drives in Windows XP - This article describes the Microsoft Windows XP Service Pack 1 (SP1) 48-bit Logical Block Addressing (LBA) support for ATA Packet Interface (ATAPI) disk drives that can increase the capacity of your hard disk to more than the current 137 gigabyte (137GB) limit. - http://support.microsoft.com/?kbid=303013

Older computer motherboards that have 28-bit IDE controllers are limited to installing drives with a maximum capacity of 137GB. To overcome this limit for drives larger than 137GB, many HDD manufacturers were providing a Promise 48-bit PCI controller card with each drive. The new SATA (serial ATA) hard disk drives also use 48-bit addressing in order to exceed the 137GB limit.

Note that no PC that has a motherboard dating from about 2002/2003, which runs Windows XP SP1 or higher (including Windows Vista) will have the 137GB limit. Note that no PC that has motherboard dating from about 2002/2003, which runs Windows XP SP1 or higher, will have the 137GB limit, because it will have a 48-bit controller. All motherboards with SATA-drive connectors (that support SATA) have 48-bit controllers.

To locate more information on this subject within Windows XP, enter Create a partition or logical drive in the Search box of Start => Help and Support in Windows XP. Alternatively, make use of a search engine.

Non-destructive partition management: Copy, move, resize, split, or merge partitions partitions on the fly

If you want to add and remove, merge or resize partitions without destroying the data on them, you have to make use of a third-party utility that is designed for the purpose, because the Windows disk management utilities are very limited, even in Windows XP and Windows Vista. You can use utilities such as Partition Magic, BootIt NG, and the free but difficult-to-use Ranish Partition Manager, but this free program is probably the best of them all:

Partition Logic - "Partition Logic is a free hard disk partitioning and data management tool. It can create, delete, format, defragment, resize, and move partitions and modify their attributes. It can copy entire hard disks from one to another. Partition Logic is free software, based on the Visopsys operating system. It boots from a CD or floppy disk and runs as a standalone system, independent of your regular operating system. It is intended to become a free alternative to such commercial programs as Partition Magic, Drive Image, and Norton."

You can also use the following free program developed for Linux. It is also available on the Knoppix Linux boot CD, where it began, but has now been hived off as an individual utility.

Gnome Partition Editor - GParted Live -

"GParted is an industrial-strength package for creating, destroying, resizing, moving, checking and copying partitions, and the file systems on them. This is useful for creating space for new operating systems, reorganizing disk usage, copying data residing on hard disks and mirroring one partition with another (disk imaging)." - http://gparted.sourceforge.net/

And here is a well-reviewed free partition manager:

EASEUS Partition Manager Home Edition (four stars - doesn't work with 64-bit Vista) -

http://download.cnet.com/Easeus-Partition-Master-Home-Edition/...

Windows Vista and Windows 7

Disk Management is much the same in Windows 7 as it is in Windows Vista.

To open Disk Management in Windows Vista, click the Start button and enter diskmgmt.msc in the Start => Start Search box (it's the Start => Search programs and files box in Windows 7), or click the Start button => right-click Computer and then select Manage. Expand the Storage section and select Disk Management.

Read Can I repartition my hard disk? on Microsoft's site.

The new version of Disk Management allows you to resize partitions on the fly without the loss of data. Just right-click on any partition and select Extend Volume or Shrink Volume.

Full click path: Click on the Start button, right-click the mouse with the mouse pointer on Computer and select Manage. Expand the Storage section and select Disk Management. Now just right-click on any partition and select either Expand or Shrink to change the size of the partition.

How to Use Disk Management in Vista -

http://www.windowsreference.com/windows-vista/...

How To Access Disk Management in Windows 7 -

http://pcsupport.about.com/od/windows7/...

Deleting and creating partitions or logical drives in Windows XP and Windows Vista

Note that you can also use the Command Prompt (command line) to delete and create partitions/logical drives in Windows XP/Vista.To find out how to do so, go Start => Help and Support and enter create a partition or delete a partition in the Search box. In Windows XP, you will be offered these two options: Using a Windows interface and Using a command line. In Windows XP/Vista to bring up the Command Prompt, enter cmd in the Start => Run box (XP) and the Start => Start Search box (Vista).

In Disk Management within Windows, right-click with the mouse on the drive's graphical entry to choose the operation (partition or format) that you want to perform. For Windows XP/Vista, the best choices are a 4KB cluster size and the NTFS file system. Note that those options are greyed out for the boot drive, which is usually the C: drive, because you cannot format the drive that Windows is running from or delete its partition.

You can easily remove any other logical drive or partition by using the Delete Logical Drive option.

If there is an unpartitioned, unformatted space on the drive it will be represented by a box that you can partition by using Create Logical Drive and then Format. Windows gives a new logical drive a drive letter automatically, but there is also an option that allows you to choose the drive letter.

The Disk Management feature in Windows Vista (but not in Windows XP) can perform all of the functions of the version in Windows XP, but it can also resize partitions on the fly without destroying data. Read Can I repartition my hard disk? on Microsoft's site.

But the best way to perform those actions in an emergency in a Windows XP/Vista system is to boot from its installation CD/DVD (if your PC came with one, or you purchased your own). You may have to enable the CD/DVD drive as the first boot drive in the boot order in the BIOS setup, because the system won't boot from a CD/DVD unless its drive is the first boot device in the BIOS. You do this by choosing the Windows Setup option after the system has booted from the CD. It asks you if you want to reformat the boot partition.

Note that the system recovery discs for Windows XP systems of some vendors/ PC manufacturers only function on a FAT32 file system, apparently because they don't want to incur additional support costs from having ignorant users running into trouble if they enable the extra security measures that Windows XP running the NTFS file system allows. Therefore, if that is the case and you convert a drive from FAT32 to use NTFS, you won't be able to use the system recovery CD/DVD.

That could still be the case with brand-name PCs that have Windows Vista preinstalled by the manufacturer and that come with a recovery CD/DVD. In any case, you can easily check which file system is being used by the hard drive(s) installed in a system. In Windows XP, open My Computer and in Windows Vista open Computer. You might have to right-click on an empty space in the window, click on View in the menu that comes up, followed by Details, and then click on the bar that shows the attributes (Name, Types, Total Size, etc.) to enable File System.

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How to copy/transfer files from and old to a new hard disk drive

The first version of Windows 95 used the 16-bit FAT16 file system, which could only address a hard disk drive (HDD) or a partition on a HDD of only 2GB in size, because 16 bits of information can only be arranged in a file system to address that much data at a time.

The FAT32 system used by Windows 9x systems (Windows 95 OSR2 to Windows Me) uses 32 bits of information at a time, and, because of technical rather than limitations on the size of the file system, it can only properly address drives of up to 64GB in size.

But HDDs of 250GB and larger are now common, and tools such as Defrag and the DOS Chkdsk were not designed to handle drives of a capacity larger than 64GB, so loss of data is likely if they're used on volumes or partitions larger than that limit in Windows 95/98/Me (Windows 9x) systems.

Note that the Chkdsk HDD utility that is part of Windows XP and Windows Vista (the equivalent of the ScanDisk utility that comes with Windows 9x systems), can be used with any of the latest large hard disk drives.

In Windows XP, Chkdsk can only be used from the Command Prompt (Start => All Programs => Accessories) or from Start => My Computer => right-click the drive that you want to check, and then in the menu that comes up click Properties => Tools => Error-checking, or by running Windows XP's Recovery Console. Click here! to visit information on it on the Recovering Windows XP page on this site.

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.

If you want to transfer files from one computer to another, you should use the data-transfer utility that came with the retail boxed hard disk drive, or download it from the drive manufacturer's site if it's an OEM product.

Western Digital calls its data-transfer utility Data Lifeguard a version of StorageSoft's EZ Drive, which can partition and format a HDD. You can also use the Files and Settings Transfer Wizard in Windows XP or Windows Easy Transfer in Windows Vista and Windows 7. More information on them is provided below.

Note that FDISK, the MS DOS partitioning utility that comes with DOS and Windows 9x, cannot be used with Windows 2000/XP/Vista, which have their own partitioning and formatting utilities that are run from their setup CD/DVD or from within those versions of Windows.

Click here! to go to some very useful information on FDISK on this page. Use your browser's Back button to return here.

You can also use XXCopy (free for personal use) from xxcopy.com, because it supports all of the versions of Windows.

Windows XP: Files and Settings Transfer Wizard

"...I was pleased to find that my new Windows XP based computer includes a Files and Settings Transfer Wizard that even this sceptic finds truly wizard. In just a few steps you can move all your precious files and even more precious settings from one machine to another. Even if you don't have a new computer, use the Files and Settings Transfer Wizard to create a backup copy of your files and settings, which can then be used to restore your detailed configuration data if you ever need to reinstall Windows XP. Even if you don't have a new computer, use the Files and Settings Transfer Wizard to create a backup copy of your files and settings, which can then be used to restore your detailed configuration data, if you ever need to reinstall Windows XP". - Microsoft

Click here! to read the page devoted to the Files and Settings Transfer Wizard on this site.

Using "Windows Easy Transfer" Windows Vista and Windows 7

Windows Easy Transfer allows you to copy all your files and settings automatically to an extra hard disk drive or other storage device and then install Windows Vista. It saves the files and settings on your upgraded PC and then reinstalls them after Vista has been installed. Unfortunately, all of your applications will have to be reinstalled from their CD/DVDs in order to register them with the Windows Registry.

Windows Easy Transfer [Applicable to Vista and Win7] -

http://windows.microsoft.com/en-us/windows7/products/features/windows-easy-transfer

See this article on this site: Windows files systems: FAT32 versus NTFS.

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The FDISK utility

The FDISK utility is provided by Microsoft to partition and format hard disk drives in Windows 95/98/Me.

Visit this MS Knowledge Base article - 255867 - How to Use the FDISKTool and the Format Tool to Partition or Repartition a Hard Disk, here:

http://support.microsoft.com/?kbid=255867

Note well that if you have a HDD of 64GB or more, if you are using the MS FDISK utility to partition it, you have to use the latest update of the FDISK.EXE file.

To read an article called FDISK Does Not Recognize Full Size of Hard Disks Larger than 64 GB,access the MS Knowledge Base here:

http://support.microsoft.com/?kbid=263044

The updated version of FDISK has never been issued through the Microsoft Update facility.

Fdisk.exe (FDISK) Unable to Partition Drives Larger Than 512 Gigabytes -

http://support.microsoft.com/?kbid=280737

You should also read the following related document that deals with the DOS file, Format.com, which displays the size of the HDD incorrectly:

http://support.microsoft.com/?id=263045

Note that even the updated version of FDISK doesn't allow you to enter partition sizes that are larger than 99,999MB (approximately 100GB) unless you enter the partition size as a percentage of the drive size. In any case, there is some annoying display corruption when partitions are larger than 99,999MB. It also can't use 48-bit addressing, which is needed to access drives that are larger than 137GB. HDDs of 137GB and larger raise several other problematic issues.

You are therefore advised to use the formatting and partitioning utility that is provided by the manufacturer of a HDD, such as WesternDigital's Data Lifeguard.

Western Digital made a diskette/download of Data Lifeguard - version 10 - available that often crashes at the end of the data-copying process. At the time of writing, there wasn't a fix available on WD's website, but the older version, 2.8, works on HDDs of up to 137GB.

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How to erase the contents of a hard disk drive properly

Formatting a hard drive does not erase the data recorded on it, it merely removes the file system's reference to the data so that it cannot be accessed by the system. In Windows 9.x systems, the file system - usually FAT32 - is changed, and in Windows NT/2000/XP/Vista it is usually the NTFS file system that is changed.

The data of a formatted hard drive can be read or recovered by disk-editing or specialised forensic software.

If you want to erase the data permanently, you have to use special software that overwrites the data many times, because it can still be recovered after several overwritings. The US Government's Department of Defense standard requires that erased data has to be overwritten 7 times (US DoD seven pass extended character rotation wiping - DoD 5200-28-STD), but some programs can erase it 35 times or more.

The more data that is overwritten and the more times it is overwritten, the longer the process takes.

You should always erase sensitive private data on a hard drive if you are selling it or the computer it is installed on.

Overwriting the data once is sufficient for practical purposes, but a low-level program must be used that writes to every sector of the drive. The free erasing tools from http://www.hddguru.com/ do that.

Eraser from http://eraser.heidi.ie/ is a free utility can perform a user-selected number of overwritings, the US Department of Defense standard number (7), or the Guttman number of 35 overwritings.

You can find other free tools by using a suitable search query in a search engine. Try entering: overwrite hard disk drive or erase hard disk drive.

If you have particularly private data on a hard disk drive, the only certain way to make sure that it can never be accessed is to destroy the drive. There are videos on YouTube showing how that is done. To find them, use a search query such as: destroy a hard drive.

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INSTALLING A NEW HARD DISK DRIVE ON A "PROMISE" PCI ADAPTER CARD

If you plan on connecting the new drive to a PCI controller card made by Promise, install both at the same time. In most cases, the system will automatically detect the card, the card detects the drive and you are up-and-running. In a few cases, it is necessary to go into BIOS setup and set it to boot from an SCSI device, because even though your drive may be an IDE ATA, the adapter card makes it appear to the computer as though it is an SCSI drive. There is more information on SCSI drives further down this page.

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SCSI and serial Attached SCSI (SAS) hard disk drives

SCSI hard disk drives (and CD/DVD drives) are often called scuzzy drives. Just as parallel IDE ATA has developed into a serial standard - serial ATA or SATA, there is now serial SCSI called serial attached SCSI or SAS.

SCSI/SAS drives are hardly ever used in desktop PCs, because the extra performance they deliver, which has been severely reduced by the SATA standard, is not required by the typical home or office user. Moreover, solid state drives (SSDs) that use flash memory, might take over from both SATA and SCSI/SAS drives. Google is reported to be planning on using SSD drives in its servers.

Google Plans To Use Intel SSD Storage In Servers -

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

SATA drives are up to 1TB (1,000GB), while SCSI/SAS drives are still around 300GB. The cost per gigabyte (1GB - 1,000MB) of SCSI/SAS is about four times as much as the cost per GB of SATA disk space. SATA bit error rates are ten times that of SCSI/SAS, which is a critical statistic for servers and mission-critical systems, because errors during a RAID rebuild can cause loss of data. With SCSI/SAS you might be able to get away with using RAID 5, but with SATA you should seriously consider RAID 6. Moreover, the MTBF (mean time between failures) of SCSI is reported to be two to four times that of SATA. However, that statistic has been called into question recently in the Google and CMU white papers. SATA is point-to-point (uses a single cable per drive to attach it to the motherboard), while SCSI is a shared, parallel bus in which all of the drives are linked together. Therefore, with SCSI, a cable or drive problem can bring down all of the drives. However, note that this is not an issue with SAS, which is point-to-point (uses a single cable per drive connected directly to the motherboard). In fact, SATA and SAS drives can use the same cables.

SCSI/SAS hard disk drives require an SCSI or SAS Controller, which can be built into the motherboard, or added in the form of a PCI or PCI Express adapter card. Note that some motherboards have controllers that support both SATA and SAS drives. SCSI hard drives usually come with a controller card, because not many motherboards have an SCSI controller.

Many SCSI (not SAS) devices, such as scanners, printers, back-up drives, etc., can be daisy-chained to the controller, with the first and last device in the chain having to be terminated at the connection points that could connect another device, with a jumper-like device called a terminator, so that the controller can determine where the daisy chain begins and ends.

Each device in the chain is allocated an ID number via the SCSI BIOS. Thus, SCSI devices are more complicated to install compared to IDE devices. Like IDE drives, SCSI drives come in different versions.

The table below shows the main SCSI standards from the lowest (bottom of the table) - SCSI-2; Fast SCSI - 8-bit Narrow - to the highest - Serial Attached SCSI (SAS) - and the SCSI devices that use them.

Type	Speed	HDD/peripheral devices
Serial Attached SCSI (SAS) - (Serial SCSI)	600 MB/sec now, but 1,200 MB/sec eventually	Hard disk drives - The SAS controller can run both SATA and SAS hard drives, but an SAS drive cannot be run from an SATA connection. Click here! for more information on Tom's Hardware Guide dated April 7, 2006.
Ultra320 SCSI (16-bit Wide)	320 MB/sec	Hard disk drives
Ultra160 SCSI (16-bit Wide)	160 MB/sec	Hard disk drives
Ultra2 SCSI (16-bit Wide)	80 MB/sec	Hard disk drives
Ultra Wide SCSI (16-bit Wide)	40 MB/sec	Hard disk drives and tape drives
Ultra SCSI (8-bit Narrow)	20 MB/sec	CD-R, CD-RW, tape, removable storage (Jaz), and DVD drives
SCSI-2 and Fast SCSI (8-bit Narrow)	10 MB/sec	Scanners, Zip drives, and CD-ROM drives

The SCSI standards are broken down into normal (8-bit) mode and wide (16-bit ) mode; the latter being twice as fast as the former.

The technology of latest generation of SCSI hard disk drives is called the Ultra320 16-bit wide standard, which has a data transfer rate of 320MB/s, which is much faster than the highest data transfer rate (133 MB/s) of the latest IDE ATA 133 (UDMA 133) hard disk drives. Even the Ultra160 SCSI standard with its data transfer rate of 160MB/s is faster than the IDE ATA 133 standard. As with IDE drives, SCSI drives are backward compatible. An Ultra320 drive will use the Ultra160 mode of operation if the hardware or the controller card's BIOS do not support the Ultra320 mode of operation.

The Ultra320 standard is twice as fast as the Ultra160 (16-bit) standard, which is twice as fast as the Ultra2 (16-bit) standard, because of the employment of a similar kind of double-data-rate (DDR) and dual-channel DDR technology that is used to increase the effective speed of RAM.

Note that cheap SCSI controller cards often come bundled with SCSI scanners, etc. These are usually cut-down versions that do not have a BIOS. Such a bundled card will be fine for use with the peripheral it came with, but if you want to connect more than one SCSI device, you should obtain a card that has its own BIOS that can be accessed, enabled, and disabled.

The installation of SCSI drives is more complicated than an IDE drive, so, if you don't know how to do it, make sure that you buy a boxed product that comes with an installation manual. You can also search the web to find tutorials on SCSI configuration and installation.

Note that it is possible to buy a separate case, which looks like like a PC tower case, to house SCSI devices. It contains an interface card and one or more fans. You install all of your SCSI devices to it, and then link the case to your PC as you would any other external SCSI device. You can install up to 15 SCSI drives daisy-chained to an SCSI interface card.

To find more about SCSI, visit these sites/pages. -

How SCSI Works - http://computer.howstuffworks.com/scsi.htm

Click the title to read: How To Install and Troubleshoot SCSI Hard Drives on the Seagate site.

You can also find plenty of information on SCSI and Serial Attached SCSI (SAS) by entering a suitable search query in a search engine.

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The modes of the IDE ATA standard

The official terms for the different modes of IDE ATA hard disk drives (aka UDMA and Ultra DMA drives) - from the earliest - PIO Mode 0 (ATA 1) - to the latest - ATA 133 (Ultra ATA Mode 6) - and some of their technical details are as follows:

DMA Transfer Modes	Data Transfer Rate (max.)	Cable	Cable Conductors	CRC
PIO Mode 0 (ATA 1)	3.3MB/s	40-pin IDE	40	No
PIO Mode 1 (ATA 1)	5.2MB/s	40-pin IDE	40	No
PIO Mode 2 (ATA 1)	8.3MB/s	40-pin IDE	40	No
PIO Mode 3 (ATA 2)	11.1 MB/s	40-pin IDE	40	No
PIO Mode 4 (ATA 2)	16.6MB/s	40-pin IDE	40	No
Ultra ATA Mode 2 (ATA 33)	33.3MB/s	40-pin IDE	40	Yes
Ultra ATA Mode 3	44.4MB/s	40-pin IDE	80	Yes
Ultra ATA Mode 4 (ATA 66)	66.6MB/s	40-pin IDE	80	Yes
Ultra ATA Mode 5 (ATA 100)	100MB/s	40-pin IDE	80	Yes
Ultra ATA Mode 6 (ATA 133)	133MB/s	40-pin IDE	80	Yes

The data transfer rate is measured in megabytes per second (MB/s). The 80-conductor cable has to be used for a drive that supports Ultra ATA Mode 3 and higher modes. The 40-conductor cable can only be used with drives up to Ultra ATA Mode 2, but the 80-conductor cable can also be used with those drives. Ultra ATA 33 introduced CRC (Cyclical Redundancy Check), a feature that provides data-protection verification. Ultra ATA 66 and Ultra ATA 100 and Ultra ATA 133 use the same process, and support all previous DMA transfer modes. There are no Ultra ATA Mode 3 hard disk drives; it is only a mode that ATA 66 and higher drives support. There are only ATA 33/66/100/133 hard disk drives.

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Information pages on hard disk drives and how to install, partition, format and troubleshoot them

If you want to find out exactly how a hard disk drive works visit the first link. It is not a complicated business installing a hard drive, especially an SATA hard drive. Click here! to go to the information on this site on how to install IDE and SATA hard drives. If you require more information, the other links go to relevant articles and a PDF file download on how to install hard drives. Some of them provide extra information such as how to partition/format and troubleshoot them.

You can find many other pages by making use of a search engine. For example, the search query install sata hard disk drives will bring up many links.

How Hard Disks Work - http://computer.howstuffworks.com/hard-disk.htm

How To Install and Troubleshoot Serial ATA (SATA) Hard Drives -

http://knowledge.seagate.com/articles/en_US/FAQ/196291en

Western Digital Serial ATA [SATA] Hard Drive Installation Guide - 001

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

How IDE Controllers Work -

http://computer.howstuffworks.com/ide.htm

Hard Disk Drives [IDE ATA] - How to install them:

http://www.tweak3d.net/articles/howtoinstallhd/

Hard Drive Upgrade Install Guide [IDE ATA] - http://www.harddriveupgrade.com/

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Hard disk drives: Reviews

Disk Drive Reviews - http://www.itreviews.com/category/hardware/storage-devices/

Storage Review - http://www.storagereview.com/

Expert Reviews

Expert Reviews - storage reviews - http://www.expertreviews.co.uk/storage

The above page on the Expert Reviews website provides reviews on the following storage devices:

• Internal hard disk drives
• External hard disk drives
• DVD/Blu-ray drives
• Network attached storage
• USB flash drives

Anandtech.com

Storage devices reviewed - http://www.anandtech.com/tag/storage

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IDE and SCSI CD/DVD Drives and Floppy Disk Drives

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Hard Disk Drives CD/DVD Drives