The real problem is when the ripple and noise causes data errors. It can FUBAR a harddrive or the BIOS. If it access the wrong address it can be as bad as a power outage during a BIOS flash. I have a Dell I think board like tha there that is destined for the trash actually.

In some motherboard manuals I remember they called it "system will hang permanently" which is about the equivalent of bricked.