Sound like air escaping when computer turned off

[John]

Hi there,

I'm not sure if this is important or not but just in the last few days I
have been hearing a high pitch noise when the computer is turned off. The
noise sounds similar to the noise air makes when it passes through a small
gap, there are sometimes noises like it is bubbling.

When I turn the power off at the socket the sound stops. I tried turning
the power on again at the socket and after a few seconds the sound started
again. As far as I can tell it is coming from around the CPU area.

Does anyone have an idea what this might be?

Many thanks!
John

 

[dylan]

Hi there,

I'm not sure if this is important or not but just in the last few days I
have been hearing a high pitch noise when the computer is turned off. The
noise sounds similar to the noise air makes when it passes through a small
gap, there are sometimes noises like it is bubbling.

When I turn the power off at the socket the sound stops. I tried turning
the power on again at the socket and after a few seconds the sound started
again. As far as I can tell it is coming from around the CPU area.

Does anyone have an idea what this might be?

Many thanks!
John

Sounds like something could be shorting out or breaking down, maybe a
capacitor.
I'd be looked for a new PSU BEFORE the thing catches fire.
Is the fan running whilst the noise is present, maybe something caught in
that ?.

 

[John]

Thanks for the reply,

I just turned it on again but it didn't start properly. The PSU fan
started then stoped a few times as if it got a little power then then the
power was cut. At that point I turned it off and cut the power from the
socket for good measure.

Do you think this is definatly the PSU?

Cheers!
John

 

[dylan]

Thanks for the reply,

I just turned it on again but it didn't start properly. The PSU fan
started then stoped a few times as if it got a little power then then the
power was cut. At that point I turned it off and cut the power from the
socket for good measure.

Do you think this is definatly the PSU?

Sounds likely, fault finding over the internet isn't easy or definitive.

If you have the expertise try to do some measuring with a DVM etc BUT in any
case it's probably not worth the trouble as the PSU won't be worth fixing.
Buy another PSU they are cheap these days and not much will be lost if it
turns out not to be the fault.

The problem with PSUs is they can go faulty themselves or any item they are
powering can also take them down so not always easy to identify the problem.

Cheers

 

[John]

I have been having some strange happenings. I got the new PSU nand it all
worked great. MyUSB keyboard is no working now though (could this have
been fried by the PSU? The computer was on for the day with no problems,
it had been turned off for 30 mins or so when my new keybard arrived. I
booted it up and when windows was nearly booted up I put a CD in the
drive, a few seconds later the computer lost all power. I have tried to on
butten but it is doing nothing at all.

Could the PSU in it's death throws have damaged my keyboard and also done
serious damage to my motherboard or CPU?

I'm not sure what to think, it ran very well with this new power pack all
day until somthing went wrong.

Many thanks!
John

 

[dylan]

..

Could the PSU in it's death throws have damaged my keyboard and also done
serious damage to my motherboard or CPU?

Sounds possible unfortunately.

Perhaps you need something like this to test the psus.

http://www.maplin.co.uk/Module.aspx?ModuleNo=32378&doy=10m11