Re fans,forget old fans, new ones are cheap enough especially if it is the beast that keeps the CPU cool, go to the puter emporium and tell the minion behind the counter what species of PCU you have and get one rated for that CPU I tried replacing the fan one that came with this new CPU I had bought for a slightly quieter one and near cooked the buggah.
If it's the power supply fan buy a new PSU they are also cheap as chips as well.
PS,it's a doddle to change a CPU fan and it's a doddle to change a PSU unit