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#41
I found another series of benches that might help the OP decide. Here's the 5870 on a few cores... not many, but enough to get a better idea.
At 1280, obviously, the i7's just kick butt with the 5870, but as res increases we can see things even out a bit. Granted, they didn't test a Q6600 (those are hard to find these days), but I think we can safely assume its results to be somewhat similar to a Core 2 Duo at 2.75GHz... not exactly the same, but very close.
May Power Be with You: Find the Best CPU for a Single ATI Radeon HD 5870 and ATI Radeon HD 5870 CrossFireX Configuration (page 6) - X-bit labs
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