When I switched over to water cooling I was worried about the same things. I run and AMD T-Bird 1.33ghz overclocked to a 1.5ghz. Now the 1.33's run cooler then their predessors (your chip) but you can expect temps between 70f and 80f, The cool thing About water cooling is that it does a lot better than HS/F when the CPU is under load. Where your CPU under load will be in the 80f to 120f. You would probably will not see 100 deg with a water colling system. I run a modified verson of the Aqua Cube(Rio 180 pump) , which has a mag-drive impeller, and goes for around 180 gallons an hour, very quiet, it is a nice pump. But when you do your water cooling, take this advice. At every hose junction use a hose clamp or two, learn about "Conformal Coating." (water proof agent for your mother board, in case of a leak)
Good Luck
