HD Tach
We tested HD Tach with the benchmark's full variable zone size setting.

HD Tach's synthetic transfer rate tests easily expose the Caviar GP's greatest weakness: performance with sequential transfers. Even the Barracudas come out well ahead of the GreenPower here, with the Deskstar a good 10MB/s in front.

At least the GP's burst performance is decent. This is more a measure of disk cache transfer rate, and it looks like Western Digital's using a similar cache on its latest Caviar and RE2 drives.

Seek performance doesn't look particularly good on the GreenPower. Despite Western Digital's claim that the GP offers the same read seek time as its SE16 and RE2, HD Tach's random access time test clocks the drive at more than a millisecond slower. The Deskstar 7K1000 has just over a two-millisecond advantage here.

CPU utilization results are within HD Tach's +/- 2% margin of error in this test.