When Western Digital introduced its GreenPower line with the terabyte Caviar GP last year, we wished aloud that the drive's new 250GB platters would make their way into a performance-oriented model. The GP wasn't even particularly slow—in fact, it was the fastest terabyte drive at the time. But by dialing back the GreenPower's spindle speed to close to 5,400RPM in a bid to improve energy efficiency, WD effectively left some performance on the table. We've been waiting to get that performance back ever since.

Unfortunately, it seems Western Digital had no plans to sate our desire for a terabyte Caviar with 250GB platters spinning at a full 7,200RPM. Instead, the company has almost done one better by launching a new batch of 7,200-RPM Caviars that pack an impressive 320GB per platter. These new drives are only available in capacities up to 640GB, so they won't challenge for the terabyte crown. With prices hovering around $130 for the 640GB model, however, this latest crop of Caviar nails the cost-per-gigabyte sweet spot that most enthusiasts covet.

The question, of course, is how this new Caviar SE16 640GB measures up. Can Western Digital's new Caviar models match up with Samsung's best-in-class SpinPoint F1? And with only two platters, does this new SE16's noise levels and power consumption compete with energy-efficient drives like the Caviar GP? Keep reading to find out.