8GB not sure, 4GB starts to load it up pretty hard, and I had trouble with 460 FSB+ stability with higher (DDR3-1500MHz +) ram speeds with my Q9650 and 2 x 2GB sticks. However if you go for 400 FSB perhaps you could get 8GB stable at DDR3-1600 MHz. It's a brilliant board though, and should be much better than what it replaced.