Noise levels
Noise levels were measured with an Extech 407727 Digital Sound Level meter 1" from the side of the drives at idle and under an HD Tach seek load. Drives were run with the PCB facing up.

If the Caviar Black has a weakness, it's the drive's noise levels. The Black ties for the loudest terabyte we've tested at idle, where it's a good three decibels louder than Western Digital's own GreenPower drives. Under a seek load, the Black is at least quieter than the Deskstar, but it's still louder than most of the pack.

Power consumption
For our power consumption tests, we measured the voltage drop across a 0.1-ohm resistor placed in line with the 5V and 12V lines connected to each drive. Through the magic of Ohm's Law, we were able to calculate the power draw from each voltage rail and add them together for the total power draw of the drive.

The Caviar Black's power consumption is admirably low, with the drive sipping fewer watts at idle and under load than all of its 7,200-RPM terabyte rivals. Western Digital's GreenPower terabyte drives consume less power, though, as they should thanks to slower spindle speeds.