i would just take a look at this thread all the way through, noting batch numbers and stuff. usual intel rule(s) is the earlier the pack date on the same stepping is best.

from what ive read, the Q746A and Q750A are a pretty good choice, E8400 and E3110 alike.

I myself have an E3110 Q746A534 waiting at home for my replacement vanilla 680i SLI on friday... shooting for 450x9 until X48