There can be 1 to more fans in most PCs. The power supply fan is common, next a CPU cooling fan and then a CASE FAN.
These are cheap to replace, but get very expensive if not replaced since other machine components will fail under the higher heat load.
1coolpc.com if they are still about has nice people you can talk to about identifying fans, connections and getting replacements.
Bob
I have an old HP 8700 pavillion (bought in 2000)that just started making noise the other day. I believe it to be a fan inside but am not very computer savvy so am leary of just taking things apart willy nilly. I did a search on this forum and came up with it being possibly a power supply fan.
Problem is that I am listening to the computer without the cover to the case on and the noise doesn't seem to be comming from the power supply. It seems to be comming from a manifold looking thing that goes from a hole in the back of the computer (thats above the power supply) and directed towards the motherboard. Is there more than one fan inside? If so how can I find a replacement for it (have been searching the web to look for specs and have come up empty handed thus far). Any help would be greatly appreciated. Thanks

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