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Upgrading: Options and Considerations

If you are running out of room for your music, graphics, or monster database files, it's time to upgrade your hard drive. But beware: Your system and its software may require some modifications before they can work with a drive larger than 137.4GB (see " Lab Notes: Big Drives May Beget Big Problems," for details).

We evaluated 14 drives from IBM, Maxtor, Seagate, and Western Digital. During our testing, Hitachi acquired IBM's hard-drive division; Hitachi Global Storage Technologies will continue to sell the Deskstar 180GXP drive we evaluated, as well as the other drives in the Deskstar line. To rank the drives, we weighed performance, capacity, price, warranty policies, and technical support offerings.

We judged Western Digital's 80GB Caviar Special Edition WD800JB to be the best overall value at just $135. At number two, Maxtor's 200GB 7200 RPM Ultra Series Hard Drive Kit offers great performance and vast capacity, for $350. In third, Hitachi's 180GB Deskstar 180GXP performed well, and its cost-per-gigabyte was the lowest of any drive evaluated. Western Digital's fourth-place, 120GB Caviar Special Edition WD1200JB offers a sweet combination of performance and capacity at a reasonable price of $200. The number five Seagate Barracuda ATA V is one of the first drives with the new Serial ATA interface; it finished third (out of 14 drives) in our performance tests. (See our chart, Top 10 Hard Drives, for more details.)

Maxtor retail drives have only one-year warranties. Hitachi, Seagate, and Western Digital offer one year on most drives but three years on their premium models (those with 8MB buffers).

You can save money by buying a bare drive--one without mounting screws, cables, or setup software--but springing for a kit that includes those pieces makes setup easier, especially for novices. (For installation tips, see " Install a Bigger, Faster Hard Drive.")

The Test Drive

PC World Test Center results fell into some expected patterns. The 7200-rpm drives we tested were usually faster than the 5400-rpm models, and using a two-drive setup with a RAID card that split data between them was faster than using a single drive of the same type for most tasks (though seek time took a minor hit). Also, an 8MB buffer (memory on the hard drive) yielded better performance than the standard 2MB buffer for disk-intensive tasks such as those in our Photoshop test.

Maxtor aced the speed tests. Its 7200-rpm Ultra Series Hard Drive Kit was the fastest parallel ATA model, and its 300GB MaXLine II--optimized for enterprise storage--was the fastest 5400-rpm drive. The company's Serial ATA-equipped MaXLine Plus II, also intended for servers, was the fastest overall. (Before we went to press, Maxtor discontinued the 200GB MaXLine Plus II drive we tested, but it will offer a similar model in the Diamond Max Plus 9 line of retail desktop kits.)

ETA on Serial ATA? Now!

We tested a pair of Seagate drives, identical except for their interfaces: One uses parallel ATA; the other, Serial ATA. In our tests, the Serial ATA model was quicker--but only the Seagate and Maxtor Serial ATA models were available for this roundup, so we can't yet say what part the interface plays in drive performance.

Regardless, Serial ATA offers several advantages over parallel ATA: Its narrow, seven-wire cables attach more easily, allow longer runs (up to 1 meter), and interfere less with airflow--thereby making smaller, more-compact PCs possible.

They permit faster data transfers, too. Parallel ATA's top rate of 133 MBps is about the maximum that the technology allows. At higher frequencies, the signals carried by one wire can interfere with those on other wires in the ribbon cable--a phenomenon called crosstalk. Serial ATA does not have such restrictions. It supports transfers of 150 MBps already; the rate will jump first to 300 MBps and then to 600 MBps over the next decade. That's far more bandwidth than current desktop drives can take advantage of, but it makes room for future growth.

Aside from raw throughput, Serial ATA has other performance enhancements, such as the ability to queue and then execute commands while the CPU performs separate tasks. Such features may have contributed to the two Serial ATA drives' fast performance in our evaluations.

RAID Means Cheap Speed

For the biggest speed boost from your hard drive upgrade, link two drives using a RAID card, such as Promise's TX2000 (for parallel ATA drives) or S150 TX4 (for Serial ATA drives). In a process known as striping, the card treats the two drives as one, thereby doubling both the number of cables available to carry data and the number of read/write heads that can be used to retrieve or record it. And striping indeed produced a handsome performance boost in our recent tests. (See our test report, Serial ATA Looks Promising , and our News & Trends story, " Hardware Boost for Hard Drives.") RAID provides a major advantage when you're working with large image, audio, or video files. On the other hand, if all you do is open or close small files, you will not benefit from RAID striping.

RAID cards cost extra (the Promise cards we used cost $100, though some cards are as little as $20). In addition, you have to purchase two drives, though you can often buy a pair of smaller drives for about the same price as a single monster drive of comparable total capacity. Another cost of RAID is a slightly slower seek time, due to the controller's having to track data stored on two drives. But that performance hit occurs only during tasks like file searches, and you probably won't notice it even then.