The best measure of dual-core versus quad-core is not speed, but price. An equivalently-priced dual-core chip will spank the same-cost quad-core chip every time.
There are one or two games coming out that will have extra programming for quad-core, but that's about it. For a gamer, I do not see any reason to buy a quad-core chip at this time. On the other hand, if you're doing video encoding, and your software is multi-core optimized, then go ahead.
But for a gamer? Pshaw. Spend the money you save on more RAM, a 10,000 RPM hard drive, a better videocard. There are zillions of little improvements that will do more for your gaming experience than two more cores which will spend 99% of their time idle.
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For the money, right now, this is the best CPU your dollar can buy. Or your shekels, or dinars, of pounds sterling, or whatever.
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