|It depends on the game, the settings, the number of displays to make a statement like that.|
Check this out.
Thats an example of GPU bottleneck. That game (Bad Company 2) utilizes multi-core CPU technology. All 4 core and 6 core CPUs are performing the same FPS at max settings. If you were to have some godly GPU setup that maximized their performance, then you would see the CPU make a difference in FPS.
Thats an example of CPU bottleneck. The game (Far Cry 2) is not as graphically demanding, and so the CPU is able to contribute to FPS. Here, we see a difference in ~40 FPS from the X4 to the i5-2500k. If you were to have a terrible GPU that couldn't keep up with the game, your CPU choice would not influence your observed FPS.
Bear in mind, those results are from an i5-2500k at STOCK speed: 3.3 GHz. You can overclock that bad boy to 4.5 GHz with a stock fan. Asus/MSI motherboards will take you there with the push of a button- absolutely no BIOS tweaking needed. If you get your hands a little more dirty, you can easily get that CPU up to 4.8 GHz (some will be lucky enough to get a standout chip that can do over 5.0 GHz). You're talking over a 40% increase in clock speed performance.
If you want to go with AMD, you can spend your money on the X4 setup now... you will be able to upgrade to a Bulldozer CPU when its released, but then you're paying more (2 CPUs + 1 Mobo) vs Intel (1 CPU + 1 mobo). The Intel LGA 1155 socket might be around for another year or two, so you could also possibly upgrade on the Intel motherboard down the line.
If I were building a new build (which I am currently) I wouldn't consider using anything but Sandy Bridge (which I am using), unless budget absolutely couldn't be stretched and performance compromise was not an issue.