3 pin molex connector full#

If you plug a 3-pin fan into a 3-pin fan port of the mobo and allow the mobo's automatic systems to control the fan speed, here's what happens. Fan connectors and the mating mobo ports have been designed, physically and electrically, so that they always will fit together with reasonable electrical connections, but the details of fan speed control are not always the same. If you don't plug the CPU fan in there, leave that fan port unused.Ī 3-pin fan plugs into EITHER a 3-pin or a 4-pin fan port on the mobo.

3 pin molex connector full#

It also allows the mobo to check that the fan is working - it will shut the system down fast if that fan suddenly stops.But because of that checking feature, if you opt to run your CPU fan straight from a Molex PSU connector at full speed, you must tell your mobo's BIOS NOT to watch that fan, or it will get very upset that there is no fan speed signal to watch.ĭo NOT plug into the mobo CPU_FAN connector ANY other fan. This ensures that the CPU cooling fan (assuming it's working properly) will run fast enough to keep the CPU at the right temperature, but not too fast so it makes more noise than necessary. _FAN port of your mobo, and let the mobo's automatic systems control the CPU fan speed. One IMPORTANT note: it is advisable to plug your CPU cooler fan into the CPU Such a system has no way for the fan's speed to be sent to the mobo. Details below.Ī 4-pin Molex connector from the PSU will supply 12 VDC to the fan at all times over 2 wires, so it always runs at full speed. Start with: all case fans are deigned to run at 12 VDC for full speed, but will run slower under the right conditions.

Quote from an old 2012 Post (Credit to Paperdoc)

Short answer to the Post above, YES, you can connect your fans to your PSU with those cables.