Hi, I decided to go for the 3.4ghz i7 CPU after all, the iMac I'm ordering (27'' top model with 768gb) is already crazy expensive, so why not go for broke. However, my only concern is heat. It's very hard to find any concrete information about the added heat that follows with hyperthreading. The only places where I find people discussing and testing hyperthreading and temperature is on overclocking and gaming forum. I'm not too sure what CPU model Apple uses, but the CPUs I've read about are the 3570k and the 3770k, which I assume are the closest (if not identical) to what Apple are using in the iMac. Have anyone researched hyperthreading and i7 CPUs vs. i5? Is there much of a difference? I would prefer to have a cool and silent running system, esp. since I'm planning to game quite a bit in Windows 7. I would appreciate greatly some informed opinions. Thanks!