In the past, we've seen hard drive manufacturers release product families that include several versions, all based on the same technology. This rather common approach results in multiple capacity points to answer varying market demands. Samsung not only offers a large selection of different capacities - Spinpoint F1 drives even as small as 160 GB are available - but it also varies the cache memory size depending on the market segment. The top models are equipped with a 32 MB buffer, all mainstream drives utilize 16 MB, and the entry-level models only have an 8 MB cache.

Western Digital Caviar GP RAID Edition, WD1000FYPS (1 TB)

Let's not forget about Western Digital's latest addition to the terabyte cycle. While the Caviar GP WD10EACS has been available for some months now, the so-called RAID Edition drives (RE) weren't available until recently. The technical specs of the 24/7 RAID Edition, which is called WD1000FYPS, are identical to those of the regular drive: 5,400+ RPM rotation speed, 8.9 ms seek (which results in 15.1 ms average access time), 16 MB cache and the lowest power requirements in the industry.

We found the performance of the WD1000FYPS RAID Edition to be very similar to that of the regular WD10EACS, although certainly not identical; the RAID Edition drives are obviously configured slightly differently. Western Digital is proud of having the best shock tolerance specifications in the industry, together with a mean time between failure (MTBF) time of 1.2 million hours. While it's hard to verify these statements as an individual customer, the RAID Edition drives are covered by a five-year warranty, while most of the other terabyte drives have a three-year warranty. Seagate is the only drive manufacturer that provides a five year warranty for all retail desktop drives.