[MTBikerTim]

It is quite easy to write a virus which can damage hardware. Biggest problem is getting something that works on more then one motherboard or brand of motherboard. The annoying thing which doesn't damage hardware but is a pain in the arse to fix is when a virus flashes the bios back to nothing. Most bioss can be written to from windows, if it's flashable you normally do it from with in an OS whether it be dos or windows it doesn't really matter (some have settings to disable this as well ). There were quite a few viruses which wiped bioses a few years ago. There have been a few viruses that set bios values to the wrong things but this normally results in a system that will not boot and do not end up causing damage. The biggest problem for these sorts of viruses is virus protection. Virus protection tends to pick them up very quickly.