Hi i have this system with a athlon 2800+ [email protected] now this was possible by one of my mods added and intake to the top and replaced the crap fan over the radiator with a vantec tornado i use a 3 1/2 inch fan buss but that is as high as you will get a 2800+ this shuttle doesnt have voltage or multi tweaks just fsb and that is what sucks case in point good little machine fast stable but not made for the overclocker!