I7 860 or 920

Core i7 860 have TDP of 95W whereas Core i7 920 has a TDP of 130W.

At full load the 920 is consuming about 20% more power; whereas at idle it is consuming about 30% more power.
 
One little drawback which i can think of at this moment is, LGA-1156 socket platform will limit your future upgrade path (i.e. if you plan of doing so couple of years down the road).

Now that out of the way, its very capable processor as well, and offers very attractive features (e.g. Hyperthreading, which 750 doesn't offer) at very affordable price, hence making a compelling case for buying this CPU.
 
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