I'm gonna go out on a limb and disagree with el_jeffe. (Sorry el_jeffe). While the raptor drives are the quietest thing on the market, they are by means going to be the loudest thing in the case. Also, in my expierence, my raptor drive doesn't run any warmer than my 7200 RPM 80 gig.
I contimplated about whether or not to upgrade to a raptor drive for a while, and finally just bought one. I was impressed. Even my boot up times decreased, the seek time is essentially cut in half, so everything is sped up. I personally opted for the 36 gig, to use as a boot drive, and use a 7200 RPM, for backup and extra data.
In the end you will have to decide if the performance/price ratio is worth it to you on the raptor drive. I personally thought it wouldn't be, but after buying one, I have since decided it was worth it.
I would get a full gig of ram, even though it is likely you won't use all of it.
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