New kits upgrade hard drives to Serial ATA

Addonics Technologies Inc. launches its Serial ATA product lineup in the US this week, including a conversion adapter that makes existing parallel ATA (commonly called IDE) and ATAPI drives compatible with the new standard.

The US$35 converter attaches to an existing IDE or ATAPI drive and lets users take advantage of many Serial ATA (SATA) features.

Serial ATA is the replacement for today's parallel ATA standard, which provides a maximum transfer speed of 133 megabytes per second. The new standard offers a faster 150-MBps speed limit at its outset (and promises a 600-MBps limit within a few years) as well as other handy features.

SATA Goodies

The major hard drive vendors are finally rolling out their first SATA-based drives. Seagate is shipping drives to US retail stores now; Maxtor says it will follow soon.

While these new drives have only a small price premium over comparable parallel versions, many users who want SATA capabilities aren't ready to ditch their current investment in parallel ATA drives, says Bill Kwong, president of Addonics.

The converter lets them continue to use those drives, while taking advantage of some of SATA's best features, he says. For example, you can use the SATA cable, which is easier to install and maneuver inside the case than today's standard IDE ribbon cable. The cable is also notably smaller, which helps promote a neater interior and better airflow and cooling inside the PC.

The converter also lets you hot-swap the drive, which means you can unplug and remove it without turning off the power and without fear of damage, he says. Today's parallel ATA drives require you to shut down the system before removing them.

The converter also supports RAID (redundant array of independent disks) capabilities. This allows simple installation of both Raid 1 (for mirroring, which creates the same image on two drives for redundancy), and Raid 0 (for striping, which uses two drives as one logical drive, spreading data over both for faster performance).

Finally, the converter also works with most ATAPI-based devices, such as CD-RW and DVD optical drives, Kwong says. Currently, no ATAPI drives offer the SATA interface, and even motherboards that support SATA come with at least one parallel ATA connector.

Noting that one SATA benefit is to improve airflow in the system, Kwong adds, "If you get the hard drive airflow problem solved, but the ATAPI devices are still using the ribbon cables, than that's defeating the purpose."

No 150-MBps Transfers

One area where the converter theoretically doesn't match up evenly with a native SATA drive is transfer rates. While a native SATA drive can burst data at up to 150 MBps, a converted parallel ATA drive will still move data only as fast as its parallel interface will allow (100 or 133 MBps). However, the sustained data rate of both types of drives is typically one-half or less of the burst rate anyway, so the differences in performance may not be that significant overall.

Early tests of single native SATA drives show none could actually use all of the 150-MBps bandwidth for data transfer.

Addonics says the converted drives provide a slight boost in performance, Kwong says.

"We've found in our lab that the serial ATA does get slightly better performance out of a hard drive over a standard parallel ATA controller," he says. That is due to limitations on the motherboard's IDE interface, he says, adding that if an older motherboard's controller supports only ATA 66, you should get a performance boost from an ATA 100 drive when you use the Addonics controller. You should also achieve a boost if you bought a parallel ATA 100 add-in controller.

In order to use a native or converted SATA drive in a PC that doesn't have an SATA interface on the motherboard, you'll need a PCI card. Addonic' will begin shipping a two-port PCI card next week, priced at US$39. A number of other vendors are also shipping affordable SATA cards.

The company will also ship a variety of products for upgrading standard drives into removable and external SATA drives. An external SATA upgrade kit will cost US$59, and an internal/external combo kit will be priced at US$89.

Australian pricing and information was not available at the time of posting.