[Solved] Odd Fan Surging on Father's PC

I'm generally decent when it comes to hardware knowledge, but this one baffles me.
My dad has an old Windows XP machine (Pentium 4) that seems to be having one of the fans surging. I'm not entirely sure which one, but I have a feeling its the vent fan in the back of the case.

What is odd is that I have replaced the fan in this exact spot about 4-5 times since we have had it. Again, I'm not sure it is this fan exactly, but I'm pretty sure. The surging reminds me of when a car is having problems idling when sitting still (hopefully someone understands what I'm saying).

I also noticed that I plugged in a fan that used the PSU cables instead of the motherboard, and it made an extremely high-pitched squeal, but I put the same fan in my computer and it was fine.

If anyone has a clue what might be going on, please let me know.
Also, before I forget: I often clean out his computer. It often fills with dirt and dust but I try to keep it as clean as I can.

Message quoted 1 times

Reply to xmsteel

Since this is a case fan we're talking about, it seems to be pretty simple to find out for sure, which one it is: computer off, pull out fan connector, computer on, noise gone?

I guess the PSU cable provides higher voltage than the motherboard connector, that's why it rotated faster and gave the high pitch.

It seems strange that this fan needed 4-5 replacement. Maybe it's the quality of the fans?

Message edited by szaboaz on 02-15-2012 at 08:06:11 AM

Reply to szaboaz

1.) Duh! That makes sense! I guess I should try that out.
2.) I'm not sure, but like I said, the same fan I put on my own computer and no longer made that noise. It seemed to be something with his computer I guess.
3.) That is always a possibility I guess, but I was wondering if maybe it had something to do with the motherboard shorting them out.

Reply to xmsteel

xmsteel wrote :

I'm generally decent when it comes to hardware knowledge, but this one baffles me.
My dad has an old Windows XP machine (Pentium 4) that seems to be having one of the fans surging. I'm not entirely sure which one, but I have a feeling its the vent fan in the back of the case.

What is odd is that I have replaced the fan in this exact spot about 4-5 times since we have had it. Again, I'm not sure it is this fan exactly, but I'm pretty sure. The surging reminds me of when a car is having problems idling when sitting still (hopefully someone understands what I'm saying).

I also noticed that I plugged in a fan that used the PSU cables instead of the motherboard, and it made an extremely high-pitched squeal, but I put the same fan in my computer and it was fine.

If anyone has a clue what might be going on, please let me know.
Also, before I forget: I often clean out his computer. It often fills with dirt and dust but I try to keep it as clean as I can.

ave a feeling its the vent fan in the back of the case.

What is odd is that I have replaced the fan in this exact spot about 4-5 times since we have had it. Again, I'm not sure it is this fan exactly, but I'm pretty sure. The surging reminds me of when a car is having problems idling when sitting still (hopefully someone unders

Message edited by Pyree on 02-15-2012 at 08:55:43 AM

Reply to peoplelone

Quote :

1.) Duh! That makes sense! I guess I should try that out.
2.) I'm not sure, but like I said, the same fan I put on my own computer and no longer made that noise. It seemed to be something with his computer I guess.

Oh, I see, I didn't catch that.

Quote :

3.) That is always a possibility I guess, but I was wondering if maybe it had something to do with the motherboard shorting them out.

I'm afraid I'll have to leave it to the electrical engineers, who are hopefully around.

By the way, is this the only free fan connector the motherboard has to offer? What type of motherboard it is? Let's consult with the manual.

Reply to szaboaz

Another thing, since we're here... as far as I know, the case fans are not so critical in the maintaining of optimal temperature.
If the noise is that bad, I would check if I can see any difference in processor temperature with and without it. I mean, if the other case fan is in good health and silent, it might be well enough even if it's alone.

Reply to szaboaz

Your motherboard will have a controller for this fan, that regulates the RPM as needed to keep the board cool. That could be going out.

The easy solution would be to not use the motherboard to power the fan. Run it off the PSU directly.

Of course, if you have a cheap PSU that's going to cause all sorts of problems. See the PSU guide linked in my sig.

Cheap fans can die fast, especially if they are allowed to pick up a lot of dust. They just aren't designed for the extra weight. I have 11 cheap fans in my water cooled setup. They are all low RPM Yate Loons, and they are dead silent... but they go out real fast, probably an average lifespan of 18 months. (Well they still work, they just get noisy)

Steps I would take, if I were working on the comp:

1. Go into the BIOS and see if there is a fan profile to be changed. See if that resolves it.

2. Evaluate the PSU and replace that as needed.

3. Test with known good fans in that position. Just plug em in and see if the surge.

4. Replace the board or just bypass the fan header by connecting to the PSU.