A friend wanted me to change his HSF for him on an AMD Thunderbird cpu. It was working fine before, and after I made the switch it started to post and then stopped. I thought maybe it was overheating and was even worried that the CPU may be fried. There was no odor and after taking the HSF off it looked fine. I removed the thermal compound and there is no sign of any damage, I can even read all of the serial numbers just fine. I reapplied the compound and tried it again but now it won't post at all. Anything I should try or does it still sound like the cpu is cooked?