[BerndHennig]

G`Day,

my 1GhZ 12`` powerbook produces a strange sound on the top left corner (above the heating openings) during any graphic "operation":

- when the background image changes
- when I move windows (realy)
- during I watch a DVD

I think it`s not the harddisk, I (stress)tested the HD, filled it, deleted the stuff, moved
the pictures etc. - but sound still remains constant.

It`s a kind of rattling with a very high frequency. I think that only the hd is in front
left but it`s not coming from hd-positioning (I can identify the sound of the hd-positioning "under" this "rattling" sound).

I didn`t had this sound from the beginning, but it`s getting from bad to worse.

Thanks for help

[Randman]

The fan?

[irus]

It sounds like a malfunctioning capacitor, most likely somewhere in the area of video chipset. There is no telling what will happen - it can go on like this for years, producing hissing noise under heavier load, or it can fail anytime.

Not very helpful, but may stimulate some thought process:
My ThinkPad developed a similar problem after a few years. Reducing GPU acceleration in Windows allowed the noise to be reduced to inaudible level.

[madmacgames]

It could also be normal... any 12" powerbook I've ever used produces a weird little sound from the top left corner around the microphone hole when doing anything graphic. You can hear it when scrolling over the dock, playing animated gifs in Safari, moving windows, etc... Most people I've pointed it out to never heard it before... It is pretty quiet and unless you listen for it, its not really noticeable... I'm not sure what it is exactly, but my best guess would be either some normal condition of the GPU or some kind of feedback coming through the built-in mic (a mic is just a speaker).