Hands-On With Next-Generation Drive

Serial ATA (SATA) drives and controllers have finally hit the scene. Should you upgrade? SATA offers numerous technical advantages, but the 10 to 15 percent premium you have to pay for a drive, on top of the extra bucks for an adapter, probably won't generate a return that will appeal to most users today. But if your power desktop or server has multiple drives, the bandwidth advantages may be worthwhile.

We examined a $79 Promise TX4 controller and a preproduction, $190, 120GB Seagate Barracuda Serial ATA V drive. Our preliminary results show--and vendors admit--that for now, SATA offers little benefit over the fastest parallel ATA100 or ATA133 setup in a single-drive system.

But that's for now. SATA is the future of ATA for a variety of reasons. Most obviously, SATA allows an increase in bandwidth to 150 MBps today, growing to at least 600 MBps in 2007. (Parallel ATA has effectively hit the wall at 133 MBps.) Single-drive systems can't use all that bandwidth, but multiple-drive ones can, especially since they're the likeliest to be running disk-intensive applications. Expect even more performance gains with a RAID setup in place.

SATA also offers physical advantages for system builders and upgraders. SATA cable connectors are much smaller than their parallel-design counterparts, have no pins to be bent or broken, and take far less pressure to attach. The cables themselves are about 0.25 inch wide, so they don't restrict airflow within the PC case as 2-inch-wide parallel ATA cables do. SATA cables may run up to 39 inches long, compared with parallel's limit of 18 inches. And SATA's 3-volt architecture costs less than 5-volt parallel ATA.

Serial ATA 1.0 permits one drive per port, so you can't use the same cable for multiple drives. Motherboards and cards should offer multiple ports, however, and look for multipliers to increase those options in the future. Version 1.0 supports up to 128 drives.

The aforementioned four-port Promise adapter and preproduction Seagate drive were both stable and reliable in our trials. In comparison to its preproduction ATA100 Barracuda V counterpart, the SATA model performed well, besting the other drive in five of seven tests. It did particularly well on the throughput tests, scoring about 13 to 16 percent better than its sibling. The caveat: The SATA unit's 8MB of cache versus the ATA100 model's 2MB clearly helped most of its scores. (Performance may change once hardware and drivers are final.)

For now, SATA seems a bit pricey for the benefits it provides, and most users will be better off waiting until the middle or late part of 2003, when SATA will be widely implemented in PCs. (But you shouldn't expect parallel ATA drives--or connectors--to disappear for a couple of years after that.) In contrast, power users may want to try SATA once shipping drives become available, in about a month.

Seagate's new Barracuda ATA V hard drive is one of the first units to offer the thinner, faster Serial ATA interface.

SUMMARY

Barracuda Serial ATA V ST3120023AS Seagate (Preproduction model, not rated) Estimated street: $190