> > What I'd like to know is whether this bug is AMD processor or chipset > related.No, only disabling local apic really helps. On both ASUS and MSI nforce2 motherboards. I can even enable apic and acpi with disabled local apic (anyway with XT-PIC only) and have no troubles. The lockups seem to appear when drivers heavily employing DMA are used (as udma5 hdd or framegrabber).
Chipset and/or BIOS. AMD processors are known to work in other mobos.
You may try disabling just I/O-APIC or ACPI.