Yes mate, when you save the changes and boot up if it just sits there (no post beep) your voltages are probably too low or you may need to drop the command rate to T2, either hit the reset switch or if that doesn't work then hold in the power button, it's a matter of fiddling around and trying different settings, I spent all last weekend doing this to find my pcs "sweet spot"
It seems to be 3.0GHz and 1333MHz