I just had a strange thing happen. My XP box (Dual Xeon 3.2GHz HT/2GB/Dell Perc RAID5) just got pokey. Process Explorer showed Hardware Interrups taking 20% of the CPU. After four or five minutes, it went away and now bounces between 0 and 1.5%.

Where do I begin troubleshooting this, other than madly unplugging things if it happens again? I did unplug my card reader, to no effect. The machine doubles as a file server for two other people (hence the RAID), but I never even notice their activity in normal use.

Thoughts? Thanks.

-Zeke

First and last time I ever saw a problem like this was on a i845 machine with a Celeron 1.7GHz. It really killed that machine. Task Manager didn't really help as you've possibly found. Sysinternals Process Explorer was need to show it was interrupts.

Solution to that was a new motherboard. Probably not what you wanted to hear. That sounds like quite a new and expensive machine. That's basically the specs of our brand spankers Win2k3 file server.

My theory was that the mobo was simply generating random spurious interrupts. The OS would spend heaps of time blocking etc to service them, find out there was nothing there and then return to normal.

Interesting. I've got a 3 year on-site parts/labor warranty, so the cost is covered. I just want to have some thoughts in hand before I crawl into the Dell support tunnel.

I don't want to leap in to a new mobo if it can be helped. Could it be a network broadcast storm? I didn't check the network traffic (but I will if it happens again). It's got an Intel Pro/1000 MTW card connected to an unmanaged gigabit switch. We're at the back side of a relatively slow link (802.11g) from the rest of the network, so there's only so many possible candidates for fast junk data.

I'm just baffled.

-Zeke

Of course that now means possibly fighting to get a Dell tech out to look at it been there before. I'd be looking for software issues first though.

I doubt it's a network issue. Unplug the cable for a sec and see what happens is an easy test.

I'm a bit lost for ideas really. When it happened to me I was looking for software issues. Our PC supplier was reasonably certain it was the mobo - they replaced it and all was good.