Noisy PSU

[Michael]

Hello,

I live in UK and have a (Mini ATX) Pentium II approx. 5 yrs old running
Win'98.
A few months ago added RAM, replaced CD Rom with CD/RW and changed processor
fan. Recently I noticed a whining noise from the 112 W PSU and I replaced
this with a 150 W PSU and now I'm getting a different sound.

The sound is more like a continuous tone similar to the old number
unobtainable tone from a UK phone or sound from testcard/colour bars on a
TV .

I've tried another PSU and the sound remains. I've also ruled out the CPU
fan by disconnecting it for a few seconds.

Apart from the noise which is barely noticeable if music is played in the
background, the machine works ok.But I am concerned about my diagnosis
especially as I have only had the problem this year. I'm wondering if the
CPU or motherboard is ageing and causing the PSU to be noisy, is this
possible ?

Mike.

 

[philo]

Hello,

I live in UK and have a (Mini ATX) Pentium II approx. 5 yrs old running
Win'98.
A few months ago added RAM, replaced CD Rom with CD/RW and changed
processor
fan. Recently I noticed a whining noise from the 112 W PSU and I replaced
this with a 150 W PSU and now I'm getting a different sound.

The sound is more like a continuous tone similar to the old number
unobtainable tone from a UK phone or sound from testcard/colour bars on a
TV .

I've tried another PSU and the sound remains. I've also ruled out the CPU
fan by disconnecting it for a few seconds.

Apart from the noise which is barely noticeable if music is played in the
background, the machine works ok.But I am concerned about my diagnosis
especially as I have only had the problem this year. I'm wondering if the
CPU or motherboard is ageing and causing the PSU to be noisy, is this
possible ?

although this may sound a little funny
you can use a small rubber tube to isolate exactly where the sound is
comming
from.
just put one end in your ear and use the other end to "snoop"

 

[Noozer]

Apart from the noise which is barely noticeable if music is played in the

background, the machine works ok.But I am concerned about my diagnosis
especially as I have only had the problem this year. I'm wondering if the
CPU or motherboard is ageing and causing the PSU to be noisy, is this
possible ?

Videocard fan? Chipset fan (if you have one)? Hard drives? CD in the CD
drive?

The rubber tube idea is a good one but you should be able to isolate it
without.

 

[Jimmy]

Hello,

I live in UK and have a (Mini ATX) Pentium II approx. 5 yrs old
running Win'98.
A few months ago added RAM, replaced CD Rom with CD/RW and changed
processor fan. Recently I noticed a whining noise from the 112 W PSU
and I replaced this with a 150 W PSU and now I'm getting a different
sound.

The sound is more like a continuous tone similar to the old number
unobtainable tone from a UK phone or sound from testcard/colour bars
on a TV .

I've tried another PSU and the sound remains. I've also ruled out
the CPU fan by disconnecting it for a few seconds.

Apart from the noise which is barely noticeable if music is played in
the background, the machine works ok.But I am concerned about my
diagnosis especially as I have only had the problem this year. I'm
wondering if the CPU or motherboard is ageing and causing the PSU
to be noisy, is this possible ?

Mike.

I have used a PC microphone as a stethoscope to locate and isolate noise.
Works fine with or without headphones.

Jimmy

 

[Spajky]

A few months ago added RAM, replaced CD Rom with CD/RW and changed processor
fan. Recently I noticed a whining noise from the 112 W PSU and I replaced
this with a 150 W PSU and now I'm getting a different sound.

The sound is more like a continuous tone similar to the old number
unobtainable tone from a UK phone or sound from testcard/colour bars on a
TV .

I've tried another PSU and the sound remains. I've also ruled out the CPU
fan by disconnecting it for a few seconds.

Apart from the noise which is barely noticeable if music is played in the
background, the machine works ok....

looks like that some choke or transformer starts "ringing" or some
dryed capacitor starts "singing" ... for first is no problem, just
annoying ...