Power Supply Ticking Noise

Archived from groups: comp.sys.laptops (More info?)

> Last night Inoticed that when the laptop was turned of the power supply was
> making a loud ticking noise, if I unplug the power supply from the laptop it
> stops or if I unplug the supply from the mains it stops.

It depends, really, on exactly how loud it is. The power supply, being a
switchmode power supply, is sophisticated, and depending on the required
power output it changes modes. When the laptop is off and doing nothing,
it still takes a tiny amount of power from the power supply. The power
supply will thus switch on very briefly but often, which is the ticking
noise you describe. So that's the idea.

>
> Any ideas ? ?
> Is this unsfae to use ??

If it is very loud, it could mean that it's not in great condition and
may need to be replaced. I doubt that it is unsafe if you are near it,
but there is a small possibility that it would be a fire risk so
probably don't leave it unattended unless you're confident it's ok.

Summary: very quiet noise is ok and normal, very loud noise is possibly
a bad sign and get it looked at before you leave it plugged in by itself.

Cheers, hope that helped a bit though I know it's far from conclusive advice
Peter