The WD Caviar Black is a performance HD. It's top of the line and one that people use as a main HD when performance matters the most. Usually a HD in today's market that's labeled with a 5400rpm is a lower end HD with price per megabyte and low power consumption and heat output as the main concerns. This is true of previous Samsung drives, WD drives, and Seagate drives. While I couldn't find a review of the Samsung Spinpoint but I'd put money and say that it likely won't perform much better than other "economy" or "green" HD's and will get pounded by a top of the line performance HD like the Caviar Black series.