After one night of Prime95 running my G0 Q6600, it's 100% stable at 3.4 GHz, 1.375v (I raised it a bit to be sure, might be able to run at lower voltage). Temp is 52C on the hottest core with a Thermalright SI-128 and Silverstone FM121 fan. Ambient is 30C (take this into consideration).

Cannot run higher due to my Bad Axe 2 limitation so I'm looking to get a P35 motherboard and push it higher. The temps is good, a bit colder than B3 reports.