I don't know how much current can the Conroe865PE deliver to the socket but I don't think it's enough for 3.4Ghz. Most I've managed is 3.25Ghz (271x12) on my QX6800 but it isn't 100% stable, Crysis 2 manages to crash it from time to time and IBT crashes it almost instantly. I prefer to run it at 3.16Ghz (287x11) for the increased memory bandwidth. The chipset in my board can run up to 290Mhz before the board refuses to boot up so either the CPU won't clock higher or the board can't deliver enough watts to cover the increased current load. Still a QX6700 running at >3GHz is no slouch. Maybe a G0 QX6800 could run a little bit faster as it has a 10w lower TDP but they are going for about $150 right now so I don't think is worth the expense. Maybe in a couple of years when they get to $50 or so I might snatch up one.