I top out my OS/Programs drive around 300GB. That's with most of my games installed including the Star Wars: The Old Republic beta client which is 27.2GB (and I have the other one that's 51GB on the C: drive right now as well). I'm fairly certain that even the new raptors in RAID-0 don't tpo out SATA II let alone SATA III. Just get one of these instead of the two raptors for $440 and you'll probably be fine.