I've seen P4's where the thermal compound has set like concrete, undo clip, lift heatsink chip comes out of locked ZIF socket attached to heatsink.
One was so bad I had to manufacture a tool to extract it, basically took some 12ga steel, nibbled a notch big enough to fit around the heatspreader, went down the road to the locak auto electrician, put heatsink in vice, slipped "tool" over chip, twisted, chip came free (previously I'd tried many different things to get it off with no success)
On a related note, the thermal design in SuperMicro 1RU machines (at least the P4 era anyway) is complete and utter S4. We had 3 heatsink fans die in ours (cooked), I ended up drilling a fan vent over the chip (note to SuperMicro, fans don't work very well when they only have ~2mm of clearance), haven't had one die since. |