Hi all, I did some cleaning on my* PC today with some canned air. I took the CPU fan off and cleaned it. When I had replaced it all and turned the PC back on, it said I had installed a new processor. It asked if I wanted to keep the default settings or set my own new settings. I went with the defaults. PC started fine, I checked in My Computer and it said it was the same CPU as always. After about 5 minutes it shut down completly. Turned it back on, and the same happened again after a while. So I took it back out and cleaned up the connection between the CPU and the heatsink on under the CPU fan. There was what I assume was some thermal paste .... well past it .... so got rid of it and polished off the surfaces with nothing more than a bit of breath and my sleeve. Turned the PC back on an it lasted a while, even a bit of Oblivion playing, but again, after about 10 minutes it died. I am assuming the CPU is overheating. I have ordered some Arctic Silver to replace the horrible mess that used to be there which I rubbed off. Basically, I'm hoping some very nice person will say, 'Yes, you should have left it alone you fool, but replacing the thermal paste should make the problem vanish.' Any takers? *It's not the PC in my System Specs. It's a friends PC. Intel CPU, dual core, 2.4Ghz per core, not overclocked. Sorry, I don't know what model number it is.