My MB does support 3gbs Sata,which is what I am using currently (WD 250bg, sataII, 16mb cache).

So basically my optiosn were gett a really fast Raptor for just the OS and give up another 250gb...or get another 250gb (SataII, 16mb) and give up a really fast Raptor.

If I understand you correctly I should probably just get another 250 and partition the two drives. Liam, do you think partitioning the OS on a 250 will really get things slick again? Becuase my original HD is not partitioned, whcih is why I need to get another HD!