DPC's what are they?

Hi, every1.

I've recently built a new system which i'm almost happy with......

In process explorer I am constantly loosing 30% of my cpu to DPC's.
If i'm running in HT mode, thats 60-70% of the first core!
I've scanned for malware, adware, virus's, turned services on/off, updated drivers, defrag, ran registry cleaners/optimizers, re-installed windows, updated bios, pretty much everything i can think off except sending the cip back to intel. Temps are all fine.

Any ideas would be grateful.

Hiper Type R 580 Modular
P4 3.06 em64T
Abit aw8
leadtek 7800gt
1gig DDR2 533
IBM desktar 160gb

 

Ok, now i'm having second thoughts about wether or not it is the CPU.
Windows appears to be fine, until i load any app. After this the DPC's start to climb.

I'm trying to contact A-bit (should be a laugh), wondering if its anything to do with uGuru or maybe the PCI-e soundcard......