Smoking case fan

I just casually turned on my PC this early morning when the case just started smoking up like crazy like an incinerator during the BIOS. Luckily I was quick on the UPS and turned it off in a split second I hypothesized that it was the power supply but when I investigated it was actually the rear exhaust case fan because its wire was sticky and burned with the wires almost fully exposed. TO THINK IT WAS A NOCTUA FA... JUST JOKING LOOOL it was a No brand cheap case fan I got for like $2 No damage was made to the other parts luckily WEW but I think another few seconds and my rig would be on fire I never knew that that could happen to fans, I dont know also if it was gradual deterioration of the wire sleeve or abrupt. Lesson learned: Dont skimp on anything even fans! Anything like this happened to you guys?

Not yet (knock on wood).

I wouldn't think a motherboard header would supply enough current to burn the wires on a fan. The MB should have shut it down. Or was the fan connected to a power supply lead?

Yup the header can supply enough power to do it Ken, it's all part of the 12V power even though it may go through a PWM controller.

If you had the fan on a fan header I think I'd not use that one again although the motor's wiring may have caused the dead short.

carwiz said:

I wouldn't think a motherboard header would supply enough current to burn the wires on a fan. The MB should have shut it down. Or was the fan connected to a power supply lead?

It was connected through a 4-pin molex

I was going to say that the motherboard fan headers are around 1-2 Amps MAX. The circuit traces are like the width of a pencil mark. Most boards makers will specify the maximum current draw for the fan headers. The controller will turn off the header if current goes above the max. Or the board will go up in smoke.