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Tabard
05-08-2014, 07:38 AM
Hi, I have a problem with my Fans on my pc. The front fan and top fan are not spinning - But in my BIOS it tells me the RPM of the fans and that everything is okay, but I can see that they are not rotating. (One is plugged into a CPU socket, is that a problem?) And they stopped working at the same time, so I kinda dismissed it was a hardware problem - But I cant figure out what is wrong. Can anyone help me?

Thanks!
Tabard.

pctek
05-08-2014, 08:29 AM
Hi, I have a problem with my Fans on my pc. The front fan and top fan are not spinning - But in my BIOS it tells me the RPM of the fans and that everything is okay, but I can see that they are not rotating. (One is plugged into a CPU socket, is that a problem?).

What fans exactly? Case fans? PSU fans? CPU fans?
The CPU fan is the only one that should be connected to the CPU fan pins on the motherboard, and if it isn't going, then your CPU will be cooked.

1101
05-08-2014, 10:02 AM
Sometimes (often) , the bios wont be monitoring case fans
Some fans might be temp controlled, ie wont turn on untill needed .

The CPU fan might be plugged in somewhere else. It should be plugged into the CPU fan connector, so that the system can monitor it correctly.
The case fans may have both become unplugged or both be on a connector that has gone bad.

Speedy Gonzales
05-08-2014, 10:07 AM
Altho there are 4 pin fans that can plug into the CPU fan header. So they're daisy chained. But you have to connect them the right way

Agent_24
05-08-2014, 04:22 PM
I can see that they are not rotating. (One is plugged into a CPU socket, is that a problem?)

Well there's your problem, you're supposed to plug the CPU into the CPU socket, not a fan! ;) :lol:


But seriously... The BIOS will only display the speed of a fan if:

1) The fan has an RPM sensor
AND
2) That RPM sensor is connected to a fan header on the motherboard somewhere
AND
3) The header that it is connected to has RPM monitoring hardware to read the signal from the fan.
AND
4) The BIOS actually bothers to display the information (A lot of brand name PCs like Dell, HP etc and almost all laptops do NOT)


I assume when you are talking about the stalled fans you mean the front and top fans on your PC case - these are most likely daisy-chanied from a PSU hard drive connector and have no RPM sensors and are not connected to the motherboard. Suspect a loose wire\connector somewhere.

The RPM sensors your BIOS will be reading will be some other fans that are connected to the motherboard.