Re: Trying to make headway into finding the Xid crashes source...
The performance degrading intrigued me, so I turned acpi back on. nvidia still has its own IRQ, but doom 3 produces 5% higher FPS. And runs stable, for that matter.
So, for me noacpi/noapic aren't needed to get the game working, its just a help coercing the computer in changing the interrupts.
I've only had one more XID since I've changed the IRQ layout, and that was winter overclock / summer temperature related.