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I've been thinking about this myself as a 3570k user I have been looking at a change upto a 3770k or a xeon although im only running a single 7950 at the moment im looking to change in the near future when the over priced amd cards come back down to a realistic price, I would imagine that maybe the op is only running a single monitor at 1080 like myself so even though you may lose a bit of performance from only having the four threads and having sli or crossfire both cards wont perform as well as they may do with an 8 threaded cpu ? if your just gaming for the fun of it would it be really be worth the hassle unless your benching and chasing every last point or mark ?