I am running Dual 248 opterons & I must say that they Crank. They make for a very gutsy Combustion machine. So far the system has been stable, Although I did have some issues with my frambuffer (Decklink Extreme) & have disabled it until the drivers are revised. But this is noting to do with the CPU's. This is my first non Intel system & to tell I properly wont go back to them in a hurry after experiencing the 248's.