You wait ages for a 1TB drive then four come along at once. However, the Western Digital version is a little different from the other trio of terabyte terrors. 'GP' stands for Green Power rather than Grand Prix, although we're sure Western Digital won't be too upset if you make the mistake. The GP's IntelliPower system allows the drive to vary its rotational speed dynamically between 5,400rpm and 7,200rpm as required. This enables it to consume just 4W when idle, half the amount consumed by most other drives in its class.

You might expect the varying rotational speed to affect performance adversely, but the Caviar GP performed reasonably well in our tests. It was joint fourth at loading the Relic level in Crysis, and made it into the top half of the table in the Gimp image editing test. With its 1TB stretched over four platters, it has a nominal areal density of 250GB per platter, one of the highest in this Labs test. However, the HD Tach 3 RW scores for sustained throughput were lower than expected, given the real-world performance, suggesting that IntelliPower does have some effect on speed.

The Caviar GP doesn't win the top performance accolade this month, but as it costs just under £160 - 17p per gigabyte - it's better value for money than many lower-capacity drives.

• Multi-GPU graphics - 20th June 2008
• CPU water cooling - 17th June 2008
• Hard disks - 20th March 2008
• Audio hardware - 29th February 2008
• Graphics cards - 24th January 2008
• CPUs - 21st December 2007
• Motherboards - 13th November 2007

• ATI Radeon HD 4870 - Graphics cards
• NZXT Tempest - Cases
• Nvidia GeForce 9800 GTX+ - Graphics cards
• AMD Phenom X4 9850 Black Edition - Processors
• SilverStone Crown CW03-MT - Cases
• Dell Ultrasharp 2408WFP - TFT monitors
• Asus Xonar DX - Sound cards