After adding a ram stick, I noticed my cpu fan wasn't working. The cpu was so hot you could burn yourself. I plugged the fan into another mobo & it worked fine. Back at the original mobo I found an identical plugin so I tried the fan on that & it worked fine for about a minute or 2 & that one went dead also. I tried another cpu fan (that I know works ok) on those 2 plugins and it didn't run either. What could be causing these plugins to get fried? Everything else on the board seems to be ok. I believe it is something like an MK7 something-or-other running an Athlon 500 Mhz. The fan is a 3 wire 12v 0.15 amp.
NEVER run the cpu WITHOUT HSF. You never tell us how long you have that fan running on the other mobo. My guess is that the fan is faulty that there is a short within it coils causing it to drain lot more ampere thus killing the circuitry on the mobo that supplying it. If another known good fan cannot function when connected to the two 3-pin fan connectors, then I'm afraid 3-pin fan connectors are a goner. Replace the fan and connect it to one of the power leads for hd/floppy, unless you have one more 3-pin fan connector left on the mobo. You need a 2-wire connection only as for the other lead is for rpm reading but you can still connect this lead to the 3-pin connector. Make sure you know which pin.