CPU Fan running at 100% constantly

[WafflePi]

This wasn't happening before, but ever since i put in a new fan into my system my CPU fan has been running at 100% speed constantly. Ive tried speed fan to slow it down, but speed fan can't control the speed. Ive tried unpluging everything for trouble shooting but nothing seems to work. I can't get the fan speed down. And i know the problem is not the fan because i tried another fan on the same header, both fans were running at max speed. I tried resting my BIOS by the battery method, and through the BIOS itself, but still nothing. Im starting to think that it may be a bent CPU pin? Don't think so though. Any help is appreciated. MACHINES T5026. THANKS!

 

[HEXiT]

whats the fans make and model.
sounds to me like you got a single speed fan or you havent set the right fan option in bios to either run it in pwm mode or voltage mode.

if its pwm it should have 4 pins on the power header, if its voltage controlled it should have 3.

 

[WafflePi]

whats the fans make and model.
sounds to me like you got a single speed fan or you havent set the right fan option in bios to either run it in pwm mode or voltage mode.

Well since its a pentium 4 machine there is no BIOS setting for fan speeds, and i know that the fan will go to slower speeds because it was just earlier today, but now after i turned in on, its been running at 100% for absolutely no reason. This PC isn't a computer i use a lot, but its still something i want to solve. Anyway its a cooler master fan 4pin PWM fan, not sure the model number because it doesn't say. Thanks

 

[jimmysmitty]

WHat kind of temperatures is your CPU running at?

 

[HEXiT]

there should still be a pwm option in bios.
but saying as it was working fine earlier i would check the cpu temp.
did you remove the cooler and replace the paste?
did you remove the cooler and just reuse the old paste?

motherboard make and model? (so i can look up the manual and see if it supports pwm.

 

[WafflePi]

WHat kind of temperatures is your CPU running at?

avg: 133F but the highest i ever got on this machine is a fine 154F

 

[WafflePi]

there should still be a pwm option in bios.
but saying as it was working fine earlier i would check the cpu temp.
did you remove the cooler and replace the paste?
did you remove the cooler and just reuse the old paste?

motherboard make and model? (so i can look up the manual and see if it supports pwm.

There is no PWM option in the BIOS since the motherboard is so old 🙁, its a Pentium 4 519J processor (LGA775) and the motherboard is Intel E210882 (I think, i can't tell because there is nothing that says in the BIOS and the motherboard model doesn't seem to show correctly) But anyway again the problem started after changing the direction of my rear exhaust fan to an intake. But that should have absolutely no difference in performance, so i don't know why this happened. I also know its PWM because i was able to control the fan before this problem using speed fan, my temps are avg: 133F with a max of 154F. Thanks again.

 

[jimmysmitty]

133f is almost 55c. The CPU fan would be spinning pretty fast at that since a Pentium 4 (depending on which uArch it is based on ) has a TJMax of about 67c.

 

[WafflePi]

133f is almost 55c. The CPU fan would be spinning pretty fast at that since a Pentium 4 (depending on which uArch it is based on ) has a TJMax of about 67c.

But the weird thing is that this wasn't happening earlier today, or ever for that matter. It started ever since i switched the position of one of my fans, and i have no idea why this problem started.

 

[HEXiT]

the switching of the fan direction is likely the culprit. your probably blowing heat back into the case and causing a hotspot in front of the cooler by the ram and dvd tray. which in turn has increased the ambient in the case and resulted in the cpu getting a higher reading for its normal base running temp.
which in turn will force the fan to run faster.

try turning the fan round again. it will likely solve it.

 

[WafflePi]

the switching of the fan direction is likely the culprit. your probably blowing heat back into the case and causing a hotspot in front of the cooler by the ram and dvd tray. which in turn has increased the ambient in the case and resulted in the cpu getting a higher reading for its normal base running temp.
which in turn will force the fan to run faster.

try turning the fan round again. it will likely solve it.

unfortunatly this didnt help, i reversed the direction of the fan to exhaust air again, but this didnt do anything the symptoms are still the same 🙁 thanks though

 

[HEXiT]

in that case i would suggest you remove the cpu heat sync and clean it of old paste and dust. apply new and re-seat it..

 

[Paperdoc]

First of all, you misunderstand a bit how fan speeds are controlled. You are correct I'm sure that the BIOS on this older machine does not have a PWM option on any mobo fan port, and I'm sure the CPU_FAN port is 3-pin. BUT any 4-pin OR 3-pin fan plugged into a 3-pin fan port CAN be controlled by that port. The fact that your new fan is of the 4-pin type does not affect your situation.

Speed Fan is a software tool that will use whatever system your mobo has to control the speed of a fan. It does not care whether you have a 3- or 4-pin fan. It will still use the mobo's existing Voltage Control Mode on the CPU_FAN port to control its speed, as long as you set it to do automatic (not fixed manual) speed control.

Before removing the CPU cooler and replacing the thermal paste, examine that cooler carefully. Often on an older system the fins of the cooler become clogged with dust and severely impair its heat removal function. I've seen photos on this site of coolers completely blocked off with a thick layer of dust preventing air flow through it. If a thorough cleaning of the heatsink itself does not solve the problem, then proceed with the thermal paste replacement.

 

[WafflePi]

in that case i would suggest you remove the cpu heat sync and clean it of old paste and dust. apply new and re-seat it..

The weird thing about this though is that this happened all of a sudden, this couldn't have been caused by the thermal paste suddenly drying up, I've tried reseating the PWM connector, and I've just tried reseating the processor, and the heatsink, but i unfortunatly have no difference, if its worth telling you, i tried installing advanced system care 8 the day this happened. Thanks again for all your help!

 

[WafflePi]

First of all, you misunderstand a bit how fan speeds are controlled. You are correct I'm sure that the BIOS on this older machine does not have a PWM option on any mobo fan port, and I'm sure the CPU_FAN port is 3-pin. BUT any 4-pin OR 3-pin fan plugged into a 3-pin fan port CAN be controlled by that port. The fact that your new fan is of the 4-pin type does not affect your situation.

Speed Fan is a software tool that will use whatever system your mobo has to control the speed of a fan. It does not care whether you have a 3- or 4-pin fan. It will still use the mobo's existing Voltage Control Mode on the CPU_FAN port to control its speed, as long as you set it to do automatic (not fixed manual) speed control.

Before removing the CPU cooler and replacing the thermal paste, examine that cooler carefully. Often on an older system the fins of the cooler become clogged with dust and severely impair its heat removal function. I've seen photos on this site of coolers completely blocked off with a thick layer of dust preventing air flow through it. If a thorough cleaning of the heatsink itself does not solve the problem, then proceed with the thermal paste replacement.

Ive cleaned the heatsink fully about 3 months ago, because this was a hand down computer (its not my main PC though) the first thing i did was completely wipe everything and clean all the dust out, and plus my temps are perfectly normal for a pentium 4 519j, if its worth saying i installed advanced system care 8 the day that this started happening, and it started ever since i reversed the direction of a rear fan, but i don't see how any of that should effect the performance of my PC, ESPECIALLY, because i have the rear fan pluged into a molex connector and not the motherboard, but the CPU fan is plugged into a 4pin slot labeled CPU_FAN. Thanks a lot for your help!