Noisy computer

[Jimmy9190]

I have a 6 year old HP desktop here that after it is on for 30 minutes or so it starts to make a really loud noise, sounds like the fan is about to blow up. The computer still works OK, is just really loud. Two days ago I took the computer out if its place in the computer hutch while it was on and the noise was present, and when I moved it the noise went away. Then night before last the noise came back. Yesterday I hit the side of the power supply just once and not very hard with my knuckle and the noise stopped. Last night the noise was back again, loud as ever.

About a month ago I took the side panel off and vacuumed all the dirt, dust and pet hair out of it. I vacuumed the 2 fans I could see inside it and cleaned it up inside the best I could. It ran fine, was quiet until a day ago now there is this loud fan type noise.

Is there a fan inside the power supply that may also be dirty? Is it even possible to open a power supply up to clean the internals on it? And if so is it possible to replace the power supply fan? I really don't want to buy a new power supply right now.

Any help is appreciated.

 

[bepperb]

It's very easy to replace a power supply fan. Just be careful, there are some big capacitors in there. They are almost always 80mm fans, which you can buy anywhere for a couple bucks or probably pull from something else. I wouldn't mess around with cleaning it. Be careful, perhaps leave the ps unplugged overnight.

 

[barlowc]

My guess would be that the bearings on the power supply's fan are shot. Generally, the stock fans in computers aren't very good. So if you run the computer a lot like I do (i.e. 24x7), they wear out. Keeping the inside clean of dust and pet hair helps prolong the life of fans, but failure is not out of the ordinary.

The power supply generally isn't considered a serviceable component. However, if you know what you're doing, you can get a replacement fan online (e.g. Newegg.com or ZipZoomFly.com) or at a local computer repair short, crack open the power supply, and replace the fan like I did.

But simply cleaning the internals of the power supply shouldn't require opening it. I just swap/reverse the hose on my shop-vac so that it's blowing air and blow the dust out of the power supply. There's usually enough air openings in the power supply's case to "push" all the dust out like that.

 

[wavinwayne]

It could be the case fan or the power supply fan. Neither are very expensive or difficult to replace (usually). I had to replace the case fan on my 2-year old Gateway desktop recently. The new fan was less than $20, has adjustable speed, and was a breeze to install.

 

[Jimmy9190]

I took the power supply apart, removed and cleaned its fan. It was a little dusty but not bad at all. It spins freely when I spray it with compressed air from a can. I hear no noise and feel no vibration or anything when I spin the fan by hand either.

Removed and cleaned the case fan too, the big one from the back of the computer. It was a little dusty also. It has no noise or vibration when I spin by hand either. But the strange thing is the case fan on the fan itself I can pull it out away from the motor a good 1/8' of an inch. Seems there is a lot of play in it. The other fan wil move away from the motor but only by maybe 1/16" of an inch, not a lot of movement there at all.

I think maybe the case fan is bad and the power supply fan should be OK. If anyone here can help confirm this I am all ears.

Thanks very much for the help.

 

[Trav]

"when I spray it with compressed air from a can"
The way i understand it is the bearing can be damaged doing this.
From what i read in one PC mag they suggested holding the fan with a straw or similar when cleaning with compressed air.
I dont know how accurate the info is but i rather be safe than sorry.

 

[barlowc]

I've seen all kinds of "good" fans pull different amounts away from the motor, so I'm not sure I'd conclude that the one pulling away the most is necessarily the culprit.

Unfortunately, figuring out which one is bad is probably just going to take some experimentation. You'll have to let the computer run until it starts making the noise. When it does, if you have the case already open, you might be able to unplug the case fan and see if the problem persists. If it does, then you'll know it's not that fan. You might also be able to listen real carefully by putting your ear as close as possible to the different fans and see if you can hear which one is groaning. Once you figure out which one it is, it should be a relatively inexpensive repair.

 

[tomcat27]

when the computer is making the noise, simply unplug the case fan to see if the noise stops. most likely the cause is a dry, worn bearing, so cleaning it may not provide a permanent solution. it's also pretty easy to replace the entire power supply - not a bad idea since they, along with hard drives, are the most likely components to fail

 

[OVERKILL]

It is typically the bearing in the fan that gets dry. The factories are pretty "skimpy" on the oil. Take the fan out. Pull the sticker on the back of it off. There may, or may not be a rubber plug underneath which you will need to remove as well. Put a drop of oil in there. I use M1 0w40, but really, anything will work. The noise should go away.

 

[youdontwannaknow]

got to be careful when you 'vacuum' a fan.

did you hold the blades of the fan so that it does not start spinning due to the turbine action of the air rushing through its blades as the vacuum sucks the air ?
if you used a typical household vacuum on a small fan chances are you blew the bearing. the speed that the fan can reach when a 12Amp vacuum sucks air through a 1" hose can be way more than the fan bearing can handle or is designed to work.
And if the rotation of the fan while vaccuming was in the opposite direction than the intended rotation direction then that probably compounded the damage as well.

 

[xlt4me]

Originally Posted By: Jimmy9190
I have a 6 year old HP desktop here that after it is on for 30 minutes or so it starts to make a really loud noise, sounds like the fan is about to blow up. The computer still works OK, is just really loud. Two days ago I took the computer out if its place in the computer hutch while it was on and the noise was present, and when I moved it the noise went away. Then night before last the noise came back. Yesterday I hit the side of the power supply just once and not very hard with my knuckle and the noise stopped. Last night the noise was back again, loud as ever.


No problem... as I tell people at work, It's just a computer, there's no law saying you can't smack it around a little bit.

Originally Posted By: Jimmy9190

About a month ago I took the side panel off and vacuumed all the dirt, dust and pet hair out of it. I vacuumed the 2 fans I could see inside it and cleaned it up inside the best I could. It ran fine, was quiet until a day ago now there is this loud fan type noise.


The vacuum is a BIG no-no. Static builds up on the hose and it WILL zap sensitive electronics on the mother board. Better to blow it out with canned air.

 

[tmorris1]

All you have to do is stop each fan with your finger when it is making the noise. When it quits, you know which one is bad. You can replace them for $5. If you use compressed air or a vacuum, hold the fan blade with your finger so it doesn't spin so fast. Not only can you wreck the bearing, but I have seen them shatter and turn to shrapnel if spun too fast.

 

[Jimmy9190]

I got a new case fan from CompUSA today. It was one of the worst shopping experiences of my life. I installed the new fan though after having to make an extension for the wires. The wires on the new fan were too short to reach the fan plug on the motherboard.

So far so good. Computer has been running for 30 or 40 minutes now and no noises yet. And I really am enjoying the cool blue backlighting against the wall from this new fan with 4 blue LED's on it. I have no idea why it has blue lights but it does. Plus it has a manual speed control knob if I need it.

Thanks for the help. I had no idea you could ruin a fan with a vacuum. Will take everyone's advice next time I clean the computer.

 

[barlowc]

Originally Posted By: Jimmy9190
I had no idea you could ruin a fan with a vacuum.


I doubt that it was the vacuum that killed your fan. Given that it's a 6 year old computer, if it runs a lot, I bet the bearings simply wore out.