Thinkpads Forum

Hi,

My desktop PSU failed and it made a high pitch noise, which led me to check if my notebook power brick does any noise, and when I had put my ear on it I could hear a medium pitch sound. When I unplugged it (from the wall outlet) that sound had changes in it for around 20 seconds and then it stopped.

Is this sound normal? Do you have it too?

My power suplies don't make a noise I don't think but my laptop makes a slight hum when plugged in.

How's your power going _into_ the brick?

This is likely unrelated... I run off 12v alot.. Not the car, but a standalone 12v battery source. A while ago IBM was making 12v supplies that were very sensitive to the input voltage. Anything less than 11.6v in, and the brick would fry itself. I went through three of them. The last is slightly different than the earlier ones, and seems more robust in low voltage situations.

Oh yeah.. all the bricks made a whining noise right before they fried out.

jeff

Silent brick owner here.

However, the PSU of my PDA (Zaurus 5500) emits a high-pitched whine when the PDA is not in the cradle or is fully charged. That has been noted by several users, and seems to be normal (which doesn't make it less annoying).

cheers,
-- fish

Never any noise on any power brick under any input conditions except DC in. ... JD Hurst