Intel i7 920 is better
Intel's Core i7 has proven itself to be the most powerful gaming CPU option available, based on the data we have gathered. The Core i7-920 is a great choice for systems coupled with multiple graphics cards in an SLI or CrossFire configuration.
The motherboards and DDR3 RAM that the i7 architecture requires will bring the total platform cost higher than other systems, but the resulting performance should be worth the purchase price.
While the Core i5 performs similarly, there are a few applications and games that can take advantage of the Core i7 900-series' Hyper-Threading and triple-channel memory features, so spending the extra money on the Core i7-920 can pay off, particularly if you plan to overclock.
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