Q6600 is 160 pounds sterling and yes, quad core is VERY useful for gaming (check out Supreme Commander and Crysis, my overclocked E6600 (to 3.3~ GHz) has problems with them). The benchmarks do change with these games especially, with quad core, because they are multi-threaded sufficiently for 4 cores
The age of the multi-threading is upon us. New SSE codes are coming out (Super Shuffle Engines) with Penryn processors blitzing the Core Architecture in both speed at stock settings (8 % increase average) and Overclocking (3.6 GHz max ceiling on air cooling for the Core architecture, 4.2 GHz ceiling for Penryn architecture dies).
Nahalem is on the way too, with a predicted core count of 2, 4 and 8 on a single die. PLUS, these all include a tweaked version of hyper-threading, an AMD creation, which creates a virtual core using left over processing power. so in effect, a 4, 8 and 16 core CPU on a single die is on the way for a release in the third quarter this year.
The next step is from a 45 nm process to a 32 nm process, which is possible with current technology used in the manufacture of Penryn dies, and the creation of Cell Processors as CPUs. This will allow the simultaneous execution of a single thread by more than one core, without the need to divert processing power to split the thread into as many parts as there are cores. Cell Processors can also have obscene amounts of cores, high in the double figures if rumours are to be believed.
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If you dont want to Overclock, then... well.. learn how to, because that is where the Intel processors really shine. But be cautious... don't blow the processor with silly amounts of voltage, 1.45 should be the maximum you're willing to go. It also takes a long time to tweak it properly for the most efficiency.
The Q6600 G0 stepping can OC to 3.6 GHz on basic air cooling (Arctic Cooling Freezer 7 pro) and the Q6600 B3 stepping can OC to 3.3 GHz on basic air cooling. The reason is the small manufacturing difference in the G0 compared to the B3 that means it runs around 5 degrees C cooler.
For the same price, the Q6600 is a smarter purchase than the E6850, as it can easily be pushed above it, even if you get stuck with one that doesn't Overclock as much as I said (which happens, no two CPUs are the same). It is also more futureproof, by about 6 months, which is a full cycle in computer terms.
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Motherboard.
PLEASE do this:
Get a motherboard with the P35 intel chipset. Works very well with their own processors, better than Nvidia's 6xx and 7xx series motherboards. And, better than Intel's own X38 chipset, which is supposed to be better than the P35.
I would recomend the Asus Blitz Formula or the P5K premium (NOT TO BE CONFUSED WITH the Asus Blitz Extreme and P5K3 premium, which don't accept DDR2 RAM, but only DDR3 RAM, which is more expensive and not needed). These boards are a must if you want to overclock your CPU and get the most out of it.
