my computer's power supply fan is rattling and buzzing, help!

D

dennis75

Joined
Jan 2, 2003
Messages
820
hop some of you guys can help me out with a hardware-issue. this afternoon i opened up my computercase to clean things up. all dusty and stuff, so i used a vacuumcleaner to get rid of all the dust. i also used vc on both sides of the power supply, because it was loaded with dust somehow.

now here's my problem that has developed since the cleaning: every now and then when i turn on my pc the fan of the power supply is buzzing really loud for quite awhile, especially in the morning when the pc is still cold. it's very loud, almost as if i've 'booted up' a lawnmower instead of a computer.

at times when it does not buzz (thank goodness), the pc is realively quiet and functioning properly, but at frequent though erratic moments i hear the fan rattling/ticking/grinding a little......

when i look inside the opening on the outside of the pc-case (fan-side), i can see the blades of the plastic fan have lots of brown/grey goo on it and there's still some little bit dust left in the power supply case as well it seems.

is there any thing i should worry about? (shortcutting/fire/total breakdown.....?). how can i cure this, should i buy a new power supply or should i clean and perhaps even lube the axle of the fan? is it safe to dismantle a power supply, even if it's not connected to the outlet,? no remauning voltage like on some televisions? maybe i can inspect the fan?

it's an old POS computer (circa 1999), but i got no money to buy a new one, help!

dennis
 
It could be dust blown into the ps fan motor, or it could just be a wire against the CPU fan. I've had that happen before, and when it was really loud that's what it was, just a wire hitting the CPU fan.
 
If you arer a smoker, or there are smokers using your computer regularly you might see the brown goo build up on the fan. That goo may also have made your fan un-balanced. First I would try to simply clean it off. You can also put a very small amount of 3-1 oil on the axle ot the blade too, if you can get to it. Or, you can simply replace just the fan itself.

Yeah, it's all do'able. Just be careful and make sure everything is unplugged before attempting it. If you are not comfortable, then don't do it. Also, if it's a Dell computer (between 1996-2000 I think) you may want to research Dell power supplies. It seems to me that they used a different pin-out. The connectors would fit, but the pin-out was not standard. Sooooo, trying to swap out the power supply with a non-Dell one would damage your computer.

Good luck.
 
thanks guys, i'll give it a shot and check for wires at the fans and see if i can open the darn thing and clean and lube the fan and its axle.

the goo might very well nicotine-residue, because i'm more or less a chain-smoker. heck, my ceiling and curtains are proof of that too.

btw, lubing the axle cannot make it combustible because of heat, can it? and is it also possible that the axle's bearings (any at all? plastic?) might have developed play?

it's a Fujitsu computer btw. if nothing works, i can just buy a replacement power-supply with the same dimensions and watts/volts, right?

thanks again

denn
 
Wires in power supply cannot get into the fan under normal circumstances. It is defintely a bearing gone bad (those fans use el cheapo bearings) - you can either replace the fan or replace the entire PSU. Replacing just the fan is cheaper and if you aren'ttechnologically impaired is relatively easy to do (just take out the PSU, take the lid off, use your vacuum cleaner and a dry rag to clean all the dust that has accumulated inside, cut the two wires leading to the fan, replace the fan with a new one bought at your local electronics store and soldier back those two wires).

A new PSU shoudl cost ~$20-25 and is even easier to replace - just disconnect the wire batch going to the motherboard and the wires to the front switch and replace the entire thing. Note the kind of neclosure format you have (mostlikely some variation of ATX) and required minimum wattage rating for your machine and purhcase appropriate new PSU.

Oh and there is no such thing as "lubing the axle of the PSU fan" - those are piece of poo parts made to last a couple of years and then they die so you buy a new one. Decent fan(with ball bearings or magnetic bearings) would cost alot more and you'd have to "customize" your PSU but most folks only care about the final price - the cheaper the components the lower the price, hence junk sells.
 
thanks much faramir, i learn more stuff by the minute, and i though I was a computer-techy ;)

i'll look for wires near the cpu-fan first, because i've noticed this afternoon that that on is indeed quite exposed and could catch some cables.

but i must admit, the worn down fan-blade is most likely the culprit. i'm sure i can work it out now with the help you guys provided.

thanks a million!

denn
 
oh wait, i noticed one more thing the pc's been doing in the last couple of weeks. you know, a pc that is on always makes a constant humming-noise because of the fan? well, on my pc this strange phenomenon: the pitch/sound of the humming varies, sometimes it starts to sound higher and then all of a sudden it 'drops' to a lower sound/speed again?

any hints from this phenomenon to be taken?
:confused:
 
All you need is a new fan. They wear out. They can't be lubed; it's a sealed bearing, but a new fan is only a few bucks. It's held on by four Phillips screws and there are two little wires ... it's easy.
 
Some fans use bearings, others just use a teflon race and both eventually do wear out. Actually, I'm surprised they last as long as they do considering how fast they spin and for how long.

I respectfully disagree with faramir, you can oil your fans. Though it's not a permanent solution, it can, and is done by many folks myself included. It is simply a temporary "fix" that may or may not work all that great. But if your cheap and/or poor it's worth a shot until you can get a new one.

Anyhow, there should be a little sticker in the center of th fan blade, lift just a corner of it (don't tear it off completely), enough to get a drop of oil in there, then seal it back up. Just a dab of light oil shouldn't be a fire hazard or anything, remember....just a small, tiny, wee drop.

If cleaning and oiling don't work, replace the fan or power supply.
 
Here, you guys can argue with Dan over at Dan's Data regarding oiling fans.

http://www.dansdata.com/fanmaint.htm

I have done this and had good results, along with several people I know. In fact, it was the above mentioned article that caused us to try it. However, if it's really bad, it's beyond help and should just be replaced.
 
ok, think i got enough info for now to get started. i'm sure i'll get it fixed somehow. at least i got some peace of mind back regarding the power supply. thanks
 
dennis75 said:
oh wait, i noticed one more thing the pc's been doing in the last couple of weeks. you know, a pc that is on always makes a constant humming-noise because of the fan? well, on my pc this strange phenomenon: the pitch/sound of the humming varies, sometimes it starts to sound higher and then all of a sudden it 'drops' to a lower sound/speed again?

any hints from this phenomenon to be taken?
:confused:
Click to expand...

A lot of new computers use sensors on your motherboard to monitor CPU and internal case temps. The computer can then spin the fans faster if it gets too warm in the case or for the CPU. You may be hearing those fans spin faster to compensate for extra heat in the computer. I have some server (sorry IT guy) that when they first POST or boot run the fans at full speed for 20 seconds or so.

Just a thought. Hope that helps.
 
dennis75 said:
oh wait, i noticed one more thing the pc's been doing in the last couple of weeks. you know, a pc that is on always makes a constant humming-noise because of the fan? well, on my pc this strange phenomenon: the pitch/sound of the humming varies, sometimes it starts to sound higher and then all of a sudden it 'drops' to a lower sound/speed again?

any hints from this phenomenon to be taken?
:confused:
Click to expand...

This only confirms what i told you before- bearings used in one (or more) of the fans in your box are worn out. Pitch changes because fan's rotation trajectory changes over time (fan is not rotating around the virtual center point anymore, its rotation has become eccentric which is what causes the rattle).

Regarding the wire that goes close to your CPU fan - CPU fan need power to operate so that's one set of wires that gets close which cannot be avoided. There are certain connectors (squeeker, HD leds and sometimes the CD audio cable) that might or might not go close to the CPU fan as well. I suggest you use one of those plastic thingies with wire embedded in them (don't know what they are called but it's basically thin wire and a flat strip of plastic around it, it's used to hold cables together and such) to hold your cables together. Alternative is to use one of those plastic "clamps" (remember the stuff GIs used to handcuff Iraqi forces who surrendered back in 2003 ? Like that, just smaller). EIther way, keep those wires bound together and away from the CPU fan.
 
yam said:
Here, you guys can argue with Dan over at Dan's Data regarding oiling fans.

http://www.dansdata.com/fanmaint.htm
Click to expand...

Note the part that says "If you catch a deteriorating bearing before it gets too bad, though, you can make the fan live a lot longer with a few drops of oil. If you oil a bearing before it shows any symptoms, the thing can live for a lot longer than the manufacturers expected". (emphasis theirs)

I found it easier to replace the fan when it got bad 'cause my psychic senses aren't good enough to catch the point where lubricant is running low and more should be added :D YMMV.
 
I'm a A+ Certified computer tech, and I do this for a living... Just to stave off some of the rebuttals.

When you blow the dust off / out of a computer, *especially* near fans, do not let the air spin the fans. It spins them faster than the bearings are designed for and they can actually break or escape from their housing.

When you want to blow the dust out (using caned compressed air) make sure to use something like a pen or the blade of knife to keep the fan from spinning and destroying itself.

just my $0.02 CAD

your friendly neighborhood computer tech.

-G
 
knife_boi said:
When you blow the dust off / out of a computer, *especially* near fans, do not let the air spin the fans. It spins them faster than the bearings are designed for and they can actually break or escape from their housing.
Click to expand...


knifeboi: very true obviously, heheh, errrm, that's exactly what i did this afternoon. i thought it was kind of fun to rotate the fan with the suction-power of the vacuumer. when i found the sweet spot off the fan it would spin really really fast so that it made a very high rotate-pitch/sound :) .

weldon: nah, that's not it. my PC is old and it doesn't have variable-speed on the fans. nothing to see in the bios either.

faramir: you're dead on, that must be it.

anyways, i just 'did it', dismantled the whole power-supply, used the vacuumer and a brush to clean the fan an the PSU-insides, and used a toothbrush on the fan itself to get the goo off (a lot btw, funny mixture of sticky-brown-dust-kind-of-goo). i also opened up the lid behind the sticker and put quite a lot of Remington Rem Oil in it and then closed it. i think i used a little too much oil though, because it was overflowing.....

anyway, i just closed up the pc again and using it as i type and the sounds are definately reduced in both frequency of occurrence and noise-level. so, it HAS slightly improved somewhat, for as long at it may last.......( :confused: ).

when working on the fan i noticed it had a lot of play though, so will probably need a replacement soon anyway. oh well, at least i know how to do it now, thanks to you guys (love this forum! :cool:). fun tinkering it was actually :)

btw, the sticker on the fan said "May Yie Precision, DC Fan, Brushless, Sleeve Bearing")

let's see when i'll finally need a new fan, i'm guessing this thing will die soon, having rotated it with the vacuumer at 40000 rpm and all that...... ;)

thanks to all you guys for your help, it helped tremendously and i learned more stuff about PC's power supplies and fans. imagine that, getting a dozen responses within half an hour about computer-issues on a bladeforum. man, i love this place. 'knice' people :)

dennis
 
it doesn't really matter, but thanks for the sugg. craigz.

if i need one i just visit my local computer-shop.....
 
Had it happen many times at home and here at work. I usually beat it a few times with my fist and itll quiet down (no kiddin) , it may also be a sign that your PS is getting ready to take a dump.
 
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