Acer Notebook fan always at Max speed

[Geek Sonic]

Hi everyone!

I own a 4 year old Acer Notebook 4540 whose fan about a year ago is spinning always at max speed. What bothers me is its noise.

Yesterday I opened it up and cleaned up all dust inside the fan (a lot!). The noise eased, but still bothers.

I already tried the bios menu, but it is so basic. Speedfan does not work either. What I would like to know is whether there's a way to slow down the cpu fan. Thanks!

 

[volcanoscout]

Chances are the thermal paste needs to be replaced. Your fan is having to work overtime to dissipate the heat. OEM laptop producers don't normally use very high quality paste to begin with, and the application a lot of times is sloppy (I would say EVERY time based on personal observation, but I'm trying to be fair). After 4 years, especially with the last year running hot, even if they used good paste and applied it well, it would still be due for replacement.

Get yourself some good paste (IC Diamond 7, Arctic Cooler 5, Noctua NH-T1, Tuniq TX3 or 4, doesn't really matter) from your favorite computer store, some isopropyl alcohol (99% by preference, but lower purity will work), and some q-tips. If you haven't done this before, there are a ton of tutorials on youtube.

While you have the heat sink off, make sure to clean the dust out of the cooling fins very thoroughly.

I'll bet the difference is pretty dramatic.

 

[Geek Sonic]

Thank you very much for your answer volcanoscout!

I bought your idea and replaced laptop's thermal paste, however there was no effect on fan speed.

I also bought a brand new fan and replaced the old one. Surprisingly, there was absolutely no change in speed nor noise.

I also cleared cmos, but I got no change in speed.

It's strange. From the moment I push power button, the fan starts spinning at full speed, no matter laptop is cool or room temperature is below 50˚ F.

Here is a sample of the fan noise, spinning at max speed from the begining (at time 0:04 I push the power button): https/www.youtube.com/watch?v=EH9I2Ud_jPU

I welcome very much your suggestions. Thank you!

 

[volcanoscout]

Well, that's unfortunate, although I bet your temps are great. Have you tried to flash/update the bios? Or possibly the chipset driver. If that doesn't work, it may be a fault in the mobo itself - either in the fan header control run or the feed from the temp sensor. If that's the case, someone smarter than me will have to help you fix it. As far as I know, that leaves you with the choice of living with the noise or replacing the mobo.

 

[Geek Sonic]

Well, that's unfortunate, although I bet your temps are great. Have you tried to flash/update the bios? Or possibly the chipset driver. If that doesn't work, it may be a fault in the mobo itself - either in the fan header control run or the feed from the temp sensor. If that's the case, someone smarter than me will have to help you fix it. As far as I know, that leaves you with the choice of living with the noise or replacing the mobo.

Yep, I already flashed the latest bios 1.05 and installed lastest drivers.
That's sad to hear, but I would expect that since no measure worked out.

I'm planning to install some diodes in the fan wires, hoping the voltage would go down so noise is relieved. Do you think it is a good idea?

 

[volcanoscout]

That can work, you just need to make sure you do your circuit calculations correctly so you don't burn anything out and you don't end up under-cooling your CPU. You could try building in a temperature-controlled circuit using a thermistor attached to the heatsink. I've never tried any of this in a laptop, but I'm sure it can be done - just a matter of figuring out the correct components and where to put them. I've linked a PDF from Digikey to give you some ideas.

If you're interested, I'll take a look at it today and come up with some possible circuits. Do you have easy access to components?

http/www.digikey.com/Web%20Export/Supplier%20Content/ComairRotron_25/PDF/Comair_CM_ControlFanSpeed.pdf?redirected=1

 

[Geek Sonic]

Very good article, volcano. Components are not easily found here, but I can get them. If you could come up with some possible circuits that would be great! Since I am a physician, my electronics knowledge is a bit basic.