Hello... I have an early 2008 Mac Pro. I have the 320GB option and I'm running out of space. I want to upgrade to either a 500 or 750 GB hard drive. I saw this option: http://www.amazon.com/Western-Digit...LVN4/ref=sr_1_1?ie=UTF8&qid=1319944343&sr=8-1 I like the 64MB cache and it should be a slight speed bump to what I have now. I saw the drive below too.. same specs, but 750 for the same price. I think the only difference is that the first link is enterprise: http://www.amazon.com/Western-Digital-Caviar-Internal-Desktop/dp/B004CSIFFS/ref=pd_cp_e_2 I'd like to go SSD but I'd need the 480GB option and that is way too expensive at this time. Thanks!