I make it a point to always remove the northbridge cooler and clean and apply fresh thermal paste when cleaning and reconditioning any motherboard that uses a northbridge cooler. I also always lube that fan's bearing if there is a fan. I first realized the importance of this when I had an Epox 8K3A+. When I first got the board, I had little luck overclocking it by increasing the FSB, then I read a thread on an overclockers forum where someone with the same board replaced the northbridge heatsink and was then able to greatly increase the FSB. The stock cooler was held on with some really thin thermal tape, and the base of the heatsink was convex. Fortunately, the motherboard had holes for pushpins so I used a chipset cooler from another board that I filed flat, and I used Arctic Silver thermal paste. I was able to run the FSB at 209 MHz (stock was 166).