Hi Paul,

I have the same board. You can boot and work in amd64 by disabling APIC 
in BIOS.
You may need update your BIOS, my version is 902.

Juraj

paul@whooppee.com wrote:
> I'm still having no luck at all with getting my ASUS A8N5X
> motherboard
> to boot and run in 64-bit mode.  It works fine in i386
> 32-bit mode, but
> continues to suffer from the viaide1:0:0 lost interrupt
> syndrome.
>
> There's no way for me to disable ACPI in the BIOS (there's
> an entry in
> the menu, but greyed out and unselectable) and I've tried
> disabling all
> unused devices.
>
> I'm happy to help in any way I can, but anything more than
> booting up
> a kernel and reporting results is probably beyond my limited
> skill-set!
> :)
>
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