3/4 pin multi hookup fan

Marcus King

Honorable
Mar 16, 2013
5
0
10,510
Hi, I've installed a 3/4 pin connector fan as a case fan for my pc. I hooked up the 4-pin molex connector to the PSU, and I was wondering if I could plug the 3pin into the mobo as well. My mobo auto controls fan speeds, I can't adjust them myself, this is why it's hooked up to the PSU. I want to monitor the fan though and see the RPM it is running at. Would the MOBO overide the fan? Or would the fan not work at all?
 
Solution
When you plug the fan into the molex you get 12V all the time. When you plug into the mb you get varied up to 12V. You need to use one or the other.