I'm very fond of the idea of a hexacore at 4GHz! I'm pretty sure most will hit 4GHz, just about. Would need a bloody good cooler though.
not really, seen a 1090t of a friends at 4GHz at 45-50°C 100% Load on an H50 with the stock fan (and paste ¬.¬).
OP - Let me say straight off, folding I can't help you, no idea. In general I've already bought because the prices were so dirt cheap at the time especially for RAM - went with an Athlon II just to have something in there but will move up to a 965 BE later this year for as long as they're available. If you've got the time to wait, see what Llano brings so you can start from scratch. Otherwise don't go below the tweaked 870(A) chipset that has USB3 and SATA3 standard, or just pick one from the list in Frontline's post.