Thanks. I did eventually get it apart - stripped a screwhead (despite using JIS drivers) and had to hack some metal, but no major damage done ("just" ESD protection :-)). No longer under warranty... but I don't suspect the mainboard, since this problem occurred after 2 years of normal operation. It coincidentally appeared after my AC power adapter died, which coincidentally made the unit unbootable - which I fixed with BartPE (another story). Since the restore was based on a disk built off a non-laptop unit, I suspected something down in the Windows code - and found some references to interrupt storm at MSoft, which is supposedly fixed in SP2 - but I'm running SP2 and still have the problem. Sorry for the runon sentence. So I'm still no better off. Glad to hear that Dell fixed your problem.