Well the voltages you need to pump to get any high FSB at any multi is scary mate... We talked about Scan's Great White... I reread the review and it is clearly stated that it got scorching hot.. same here when I ran my Qx at 500FSB for a test, temps were about 10°C higher than the same clockspeed with a higher multi...

Eg I need 1.25Vcore for 4ghz ops on this Qx with 400FSB and 10 multi, with 8 multi and 500FSB I needed 0.12 more for the same, more PLL and FSB volts... which overal resulted in a faster rig but so darm hot too... so it would be better to go here wit 9 multi and 450-475ish FSB max... 9 multi (or lower) and 500FSB is insane for daily ops... not alone for ya CPU but also for ya mobo...