My motherboard's 3pin fans don't work. How come?

[simms]

One day with my Abit NF7-S v2.0 board I plugged in a few case fans (1 or 2, max) to the mobo's 3 pin connector. I used it with speedfan, no problems.

One day the fan just decided to stop spinning. I tried another fan, and no go. I tried plugging both fans into the 4pin adapter and it spun.

Anyway of fixing my mobo? I want to read my fan speeds and control the voltages.

 

[lenjack]

Most likely, the fans drew more current than the 3 pin header could handle, which would burn out the header. Don't know if it can be repaired, but if it can, it will be difficult.