If you remember Intel warned us about the fact that you might brake the pins of your socket T motherboard if you remove and insert the CPU many times. Actually the motherboard that we managed to "damage" in our case (Albatron PX915G Pro) had more than 30 changes of the CPU so far. Some time ago we performed a test where we inserted and removed a P4 LGA-775 CPU into the socket (without the cooler) 100 times and there were no problems witht he pins, so we can conclude that the aditional force that the BOX socket T cooler applies is probably the cause for breaking the pin of the socket. See the pictures of the broken pin here