Noise from Inside Computer Intermittently

[frogman]

Every so often and I may add probably once in every 6 months or so when I cold boot the computer sometime after the desktop has loaded a motor noise can be heard from inside the computer.

I then restart the computer and this makes no difference which leads me to believe that it's probably a fan problem, more often if I were to turn of the PC and cold boot again the noise would then be gone, but this morning the noise occurred, this time I rebooted to see what happened, and again the noise continued, but I didn't switch off the PC this time and left it running on restart, and the noise got quieter until it stopped completely and had gone.

Why does it just disappear completely on it's own, it's like it needs to run itself out till it's back running normal again, any ideas?

I would have thought that if it's down to a fan needing cleaned then it would have the noise all the time until the fan is cleaned. And it doesn't sound like a hard drive problem.

Thought please?

PS

I have had a new power supply fitted within the last 4 or 5 years.

[Ponch]

Certainly a fan. By opening the computer, you can find out wetherer it's the CPU fan or one inside the PSU. Usually there is not much to do beside cleaning it when you can see the dust. Most the time it's inside on the axe and the noise doesn't go away. When running, components get hot and the shape of parts can change slightly enough to change the noise they make.

[frogman]

Certainly a fan. By opening the computer, you can find out wetherer it's the CPU fan or one inside the PSU. Usually there is not much to do beside cleaning it when you can see the dust. Most the time it's inside on the axe and the noise doesn't go away. When running, components get hot and the shape of parts can change slightly enough to change the noise they make.

The thing is with it not happening for ages and when it does it only lasts for roughly between 1 to 3 minutes, so I would need to have the side cover off all the time which is not a good idea.

But I think you are right about it being a fan, and I am pretty sure it is the fan to the back of the tower.

Is there any special tools to clean the inside of a computer? I was told by a tech that it's best not to use the aerosols as these can blast the dust on to the motherboard.

Could the problem be the fan motor perhaps, and maybe it's running out?

Just one other thing, I subscribed to this thread, and yet I didn't get an email when you replied.

[puntoMX]

Could the problem be the fan motor perhaps, and maybe it's running out?

The fan motor is fine, the bearings are not. The fan you hear is a non-ball bearing type fan, so, it's using bushings of zinc with copper that sell lubes the bearing. Now, after some time of use the bushings have more play, so they are resonating until the bushings get in place and they stop resonating. if it borders you, replace the fan, if you don't care, it can take months if not years for the fan to get stuck. There is nothing you really can do about it, even using machine oil will work for just a short time (it will drip out any way) as those bushings/bearings are not sealed. All is done to make those fans as cheap as posible .

[frogman]

Could the problem be the fan motor perhaps, and maybe it's running out?

The fan motor is fine, the bearings are not. The fan you hear is a non-ball bearing type fan, so, it's using bushings of zinc with copper that sell lubes the bearing. Now, after some time of use the bushings have more play, so they are resonating until the bushings get in place and they stop resonating. if it borders you, replace the fan, if you don't care, it can take months if not years for the fan to get stuck. There is nothing you really can do about it, even using machine oil will work for just a short time (it will drip out any way) as those bushings/bearings are not sealed. All is done to make those fans as cheap as posible .

Yeah, if it were to happen every day then I would do something about it. It is an old machine, coming up for nearly 10 years now, and I will hopefully be in a position to purchase a new computer sooner than later.

The thing is like I explained in the OP, once this noise has done it's part it then stops and nothing is heard apart from the normal computer power noise hard drive, and the fans running.

[Zenskas]

Fans making weird noises before the noise goes away is not uncommon. It happens with cheap older fans, for some reason when they are left to spin for a little while they stop making a noise.

If it bothers you, it wouldn't be hard to find a fan you could use to replace the noisy one. Would cost you $5, or if you look through other people's retired PC's you could no doubt find a suitable fan.