GF's PC has the following mobo:
http://www.ncix.com/detail/asrock-97...3-94-72135.htm
The mobo has a bunch of fan plugs and comes with speed management software. All the fans are 3 pin, and all the plugs are 3 pin EXCEPT for the one for the main case fan, which is 4 pin. With the 3 pin fan plugged into the 4 pin plug, the software has no effect and it runs at full speed all the time and is loud as fuck. The fan can be controlled just fine if I move it to a 3 pin plug (so I know the fan is okay), but the temp control only affects the main fan.
Does this sound like a software bug, or is this a problem with having a 3 pin fan on a 4 pin plug? If it's hardware, is there anything I can do to make it work or do I need to buy a new case fan?