Well if you want a Q9550 get the E0 stepping one, I always get my stuff from
www.overclockers.co.uk they will give you advice but they will tell you what I have told you.
Just to point out that nothing really uses four cores unless you do some serious video edition or use virtualization software. I have core 2 duo E8400 and it overclocks big time, I get better bench marks than most quads but thats down to the hardware and three months it took me to review everything.
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