Umm... is it normal to have the PSU fan, not turning? PC is working

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Weird PSU issue: PSU fan not turning, but PC boots - fan replacement time?

Ok, so I got my computer back up and running after my power supply died by replacing with a spare 400W Sparkle fsp400-60gn I had lying around.

"Yay!" methinks... and has a look to see if everything starts up ok, etc which it does. So, Im going to put the top cover back on the case and I happen to notice that the PSU fan is motionless. "Holy **** Batman!" I quickly turned the thing off. PSU was totally cool to the touch, though. The PSU is from a bygone age (i.e. it is more that a couple of years old) but even my addled brain doesnt think that the PSU has some kind of "I will just turn on when it gets too hot" feature. :) ... or does it?

The PSU would be fine for the old computer its going into, but the *ahem* risk of fire/explosion/sudden-computer-death is making me worry. I know I have some old papst 80mm fans kicking about somewhere so do you think I should just try replacing the fan? :confused:

Thoughts on a postcard...
 
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I'd leave it on for a bit, keep an eye on the PSU, if it feels like it's getting too warm without the fan coming on, then have a look at swapping the fan. If it gets warm then the fan comes on, then you've got a clever sensing PSU fan.
 
Do you have a custom cooler on it? An esay way to check if its ok is to go into bios (or use a windows program, eg everest) and have a look at the temps.

PK!
 
be careful replaceing fans and dealing with psu's as melbourne stated in another thread below they retain charge even after they are unplugged

:)
 
If you're thinking about attempting to replace the fan, make peace with your creator beforehand.

Yeah I get on OK with my mum and dad :D

I know that capacitors can kill, and have changed PSU fans before (usually noisiness reasons - hence the papst fans). I will keep an eye on it tonight, and see if it explodes... Initial checking revealed that I would have to go through some well packed away large boxes in the loft if I want to find those fans I thought I had.

There is no custom cooler or any mods on it. Just havent ever had a PSU that autodetected its own temperature. And I didnt think I did own one... We will see what tonight brings.
 
If you're thinking about attempting to replace the fan, make peace with your creator beforehand.

This is true.. PSUs are so cheap, it's not worth the hassle. You need specialised equipment to ensure that the PSU is fully discharged of all its stored electricity.
 
When I got home I turned on the old computer. I watched it, and still no fan turnage. I left it alone for 10 minutes or so while I went to check here, then went back to it. PSU had started to get warm to the touch, and still no fan movement. Prodded fan (with a large wooden kebab skewer thing) in clockwise and counter-clockwise directions to see if a 'push-start' would work :) - but no luck there :( The fan doesn't appear to be stuck and moved in a normal way when pushed.

Unless they are a qualified electrician, I do not recommend that anyone ever attempts to open up a PSU for any reason since there are very high voltage capacitors in there that can give you a nasty (and potentially life-threatening) shock, and/or cause serious injury.


That being said, I know what not to touch, and have done it before so I will probably be ok. If you dont hear back from me, consider this a lesson in taking good advice when its given. ;)
 
I'm alive!

That's the first bit of good news. The bad news is that the fan sounds like a jet taking off. The other bit of good news is that there is now a working, not-gonna-go-on-fire PSU.

Somehow the internal power connector for the fan had come loose. I simply pushed it back into the socket where it obviously goes, taking very very great care to avoid the capacitors. I had a trained first aider on standby with a phone, just in case, during the procedure. (She just happened to be there though ;) ) Hmm... I may have to be stupid anyway just to replace the noisy fan after all that. It is louder than a loud thing on loudensday. There is a 3 pin fan connector coming from the PSU which I connected to the CPU fan connector on the motherboard (the actual CPU fan is powered through a molex) at some point through my testing. I wonder if fiddling with that will change anything - such as disconnecting it or connecting it somewhere other than CPUFAN1... ? Anyway, just thought Id let you know to stop you all worrying.

Cheers for the help/advice. :)
 
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