I’m using the ASUS A7N8X-X motherboard w/ an AMD Athlon 2500+ CPU (Barton core).
And yes, I do have it overclocked, but I tried it clocked normally and still had the same results. Also, it runs perfectly stable overclocked under Windows XP so I don’t think that’s an issue.
Maybe an issue with the Nforce drivers from NVIDIA?
in kernel 2.4.22, agpgart has support now for nvidia agp on nforce 1 and 2. try loading the kernel’s gart support and tell the ati driver not to use the builtin fglrx agp driver and see if that helps