I'm more of a Nvidia fan myself, however if i were you I'd go with a dual core, most computer games will not even use two cores yet alone 4 cores. You'd be better off with it plus there would be no performance increase from 2 to 4 cores it's a true waste of money for a 4 core processor unless your running a game plus using SETI at the same time.
Read this
http://www.tomshardware.com/reviews/multi-core-cpu,2280.html
Well, I'm planning on making this PC last a good while, preferably several years, and hopefully soon more games will take advantage of multiple cores. Even if I stay with the quad-core though, I'm going to overclock it to 2.5ghz, which should be enough to have most things stand on their own pretty well if it's only utilizing one core.




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