cpu fan stuck at 100%

Soldato
Joined
13 Aug 2012
Posts
4,274
I have just fixed a pc by changing the motherboard but cpu fan is stuck at 100%.

The motherboard 760gm-p23FX and I have tried updating to latest bios didn't help.

I have tried all the different fan settings and none make a difference fan is at a constant 4700 rpm.

The stock amd cpu cooler is a 3 pin plugged in to a 4 pin connector could this be the problem?

Could the fan be broken?

Thanks for any advice
 
When you say the stock AMD plug is a 3 pin into a 4 pin connector, do you mean a 3 pin fan connector into a 4 pin Molex connector, if so this is defiantly your problem, it has no fan control, it's just running full power all the time.
 
Maybe the op means the Cooler fan has a 3 pin connector plugged into a 4pin mobo header ?

Yes this,

The new motherboard has a 4 pin for the cpu fan.

Does anyone know what the problem is or could be?

I have build quite a few desktops before and know how to use bios settings and wire them up but can't seem to figure this out. Also it doesn't help that the fan is screaming in my ear when I'm playing with settings.
 
Basically with the 3 wire fan, you have positive, negative and rpm control, but no pwm control which is the 4th pin, that's the pin which is required for the computer to control the speed of the fan depending on CPU temps.

You do however have manual fan control as the rpm wire is still there, you should be able to slow the fan down to say 50% with software like speedfan.
 
I'm running several three pin fans from four pin motherboard connectors. In the BIOS I was given several speed options (12v, normal, silent and manual). It sounds like yours is running at a constant 12v, so look in the BIOS for any alternatives.
 
Basically with the 3 wire fan, you have positive, negative and rpm control, but no pwm control which is the 4th pin, that's the pin which is required for the computer to control the speed of the fan depending on CPU temps.

You do however have manual fan control as the rpm wire is still there, you should be able to slow the fan down to say 50% with software like speedfan.

I didn't get on well with speed fan the program looked a mess maybe I got the wrong version.

I'm running several three pin fans from four pin motherboard connectors. In the BIOS I was given several speed options (12v, normal, silent and manual). It sounds like yours is running at a constant 12v, so look in the BIOS for any alternatives.

I have tried all in the motherboard bios but settings seem limited it was only a £30 motherboard.
 
This cpu is an athlon x4 640 and using the stock cpu cooler.

I do have a stock cpu cooler here that's never been used off of a phenom 960t which has 4 pin and the bracket seems the same could I use that one instead?

Only reason I ask is the phenom cooler is quite a bit smaller and not sure if it would cover the whole cpu.

Thanks


Edit,

I think I have it sorted now I have taken the stock fan off the stock cooler and replaced it with a 4 pin one I had laying around.

All should be well now just need to put it back together.
 
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Im surprised the stock cooler didn't come with a PWM fan on it anyway, but I was going to suggest you just swap the fans between the coolers rather than the whole cooler itself, glad you sorted it.
 
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