boxpressed wrote:

I have a Geforce FX5500 PCI that I like quite a lot because it is a 128-bit version. The only problem is that the fan appears to get no power. At first, I assumed that the fan was dead an ordered a replacement. It didn't spin up either.

Is it common for the power to the fan header to be shorted somehow? The board looks fine, no damage. The slot pins look fine too.

I can always work around this problem with external fans or fans that tap into a molex connector, but I'd like to be able to use the intended cooling solution.

Generally when there is such an issue it is usually a diode or mosfet of some sort that has failed and fixing the problem isn't going to be easy without having the right equipment like a oscilloscope ect. You should consider an adapter that would allow the fan to run from off a molex connector for power or change to after market cooler.

I wouldn't put the effort into finding what went bad let alone fixing it unless it was something really special and next to impossible to replace, in that case I would rather pay someone with experience to do the job.

If you don't want to run the fan from a Molex connector you can always tap +12V from the card itself, by following pin A2 on the edge connector to a convenient point and wire that to the positive terminal on the fan.

nforce4max & 133MHz have the good advice. I only add that from what you wrote you haven't confirmed the fan and its replacement work. Murphy can be subtle so it's worth being thorough. Either confirm them on another source, or check the header with a multimeter. And of course these are 'diode' fans, so make sure the likely-working replacement is being connected correctly.

There might be a small 3 pin transistor very close to the fan header. One of it's pins would have continuity to the positive voltage pin on the header. If so, that transistor might be burned out. That can happen when a fan dies and starts drawing more current than the transistor can handle.

Thanks all for the great advice. I just wanted to confirm what I suspected--that fixing this would be more trouble than it is worth.

I did test the replacement fan, and it worked. I threw away the original fan without testing it, assuming it to be problem.

I found a 3-pin wire with a male connector on one end and female on the other, and I simply connected the male connector to the two-pin connector from the fan, making sure that the red and black wires were continuous (didn't use the pin connected to the yellow wire). The female three-pin connector fit on a three-pin fan header on the motherboard. The fan now works -- I hope that the solution isn't dangerous to any components.