Last week my beloved XFX 4890 heat sink fan died. Usually this is easy enough to fix (replace the fan/heat sink) but the four screws fixing the gpu bracket to the PCB will not budge. Someone said to me that they might be lock tight screws and the only way to remove them is the use a soldering iron?. Unfortunately I don't have access to a soldering iron at the moment and I would love if anyone had any tips or tricks about how to unscrew stubborn screws. Thanks.