Recently I replaced a heatsink and fan on P III after that it wouldn't boot up. After checking wires, removing all cards etc. I bought a replacement CPU. It was the identical model number to the previous CPU. I put in the replacement CPU and the computer actually booted up. The only problem now is the computer runs, (especially startup and login), VERY VERY slow. It didn't run like this before. Is it possible that although the replacement chip still works it is making the computer run VERY VERY slow? I thought either it worked or it didn't work. Please don't tell me I need to fork over and $30 and try another CPU. I Also, I did run a regstry cleanup program and still the same thing.