Aussie to keep ya CPU a long time, don't leave them chipset voltage settings at AUTO plz... my 780i ruined my first QX for sure, the other 3 I tested remained pretty stable from a few days of burn in on decent PWM equipped mobo's... and that Vdroop is horrendous... really strange it is present on the 790i too...

For your multi/voltage question a higher multi with a lower FSB should be able to maintain the same speed with a it less voltage yes... eg I need 1.28 for 8 x 500 and only 1.265 for 9 x 450 to be small FFT stable... but there are always exceptions to the rule...

Good luck with ya quad mate, cherish it... as it costs heapssssssssssssss