Attach on the sides????////v
Please go with AMD for gaming, I mean their 150 dollar processors (athlon 64 300+) kill the intel ones that are top of the line in the HL2 benchmarks.
And by the way, right now for 5k is way too much for a computer, you should look into spending around 2000
If you do, get fx55, one or two gigs ram top of the line, some SCSI Harddrives that go fast, and I would get some of the 6800ultras in SLI.
And watercooling.