For most home users, there will be no tangible benefit from Native
Command Queuing. While benchmarks may look nice, our real-world tests said
otherwise. That is not to say that NCQ is useless altogether, but for the
majority of desktop computers, you're not going to see a performance gain
as you would with a jump to a newer processor. However, in situations when
Hyper-Threading is being tapped, we saw some improvement in the results
that would not be seen without a major hardware upgrade.

http://www.viperlair.com/reviews/sto...seagate/72007/