Some time ago my mainboard somehow died and i needed a replacement. So i bought the first one suitable for my computer. It was ASUS A7V600-F (the old was A7V333-X or 300-X ? i cant remember right now) .. well it is a very crappy MB, because later i found, that this -F variant is something that should not be sold, its only for siemens built computers and asus has no support for it
It does some strange things like rebooting when i connect my phone via USB cable (had to buy bluetooth), but more important for this thread is, that i hear strange noises from the computer at certain occasions...
Sometims it is strange high pitched noise, sometimes it sounds like cd drive trying to read a damaged cd... but it does not comes from cd drives.. maybe it is the mainboard, maybe my graphics card (Radeon 9600 PRO), but it began after i installed the new MB.
It also happens just in certain situations...