I made the mistake of getting a shuttle case when they first came out. It only had one 80mm fan in it. Big mistake by shuttle. I had to put a vantec tornado fan in it just to keep the athlon mobile 2600 cpu under 50C at idle. If you don't know how loud, powerful, and annoying a 80mm vantec tornado fan is, let's just say if I would of put casters on the bottom of the case it would of shot off my desk.
There are quite a few mini-itx computers on the market that can play Crisis. We build them and test them with Crisis all the time. Now, Wal-Mart might not carry the higher end ones, but you shouldn't be looking at Wal-Mart for gaming PCs anyway.