It isn't too bad, but if you have an i7-920, you should get an aftermater HSF and look up an OC guide. With no more than adjusting the bclk, you can push 3.5ghz easily on that CPU at which point, it would be no real issue.
My i7 920 (stock - 2.67GHz) is at 3.8GHz for 3 years now using only a bclk OC with a Noctua NH-12P HSF on an ASUS P6T mainboard. I originally had a GTX 260 MAX OC video card in there and upgraded to an EVGA GTX 560ti last year. This system has been great for BF3 and Skyrim. Never on the bleeding edge but always near it.... I intended this rig to last me 5 years with 2 video card upgrades and I am on par right now.