I've spent most of the last week in IRQ hell. I built a pc for my housemate using a e6600 and a P5k-VM. The build went flawlessly but when recording there was distortion on his firewire audiophile sound card which m-audio advised us was an IRQ conflict. So we decided to change the IRQ....
So windows xp doesn't allow you to change IRQ, we tried everything including changing the HAL to standard processor and in the end bought a P5N-SLI just to avoid intel chipsets and a discrete video card.
Now his sound card works beautifully with the machine and his usb m-audio keyboard wont install. I swear I'm off to join the foreign legion if we have another compatibility issue with this build...
/end rant