Re: Gigabyte 6VXDC7 mobo (Via 694X chipset) SMP instability

Tim Day wrote:
> I have a machine with a Gigabyte 6VXDC7 mobo (Via 694X chipset) with a
> pair of 933MHz P3s and a couple of GB of RAM.  I run Debian Sarge's
> stock -686-smp kernels (2.4 series or more recently 2.6.8).
> 
> With a "nosmp" boot option (or using uniprocessor kernels) the box is
> rock solid.  But when I run in SMP mode it generates sporadic
>   "APIC error on CPUx: 0y(0z)"
> type messages, generally in pairs, every few minutes (or several per
> minute with the 2.6.8 kernel without a "noapic" boot option).
> Eventually the machine invariably locks up hard with no warning after an
> uptime of on the order of a few minutes or a few days (depending on
> kernel version, boot options, load and luck).  I've tried just about
> every possible combination of BIOS settings and boot options, memchecked
> the RAM, rearranged PCI cards and upgraded the PSU.  Nothing seems to
> help; the only way to get complete stability seems to be "nosmp" or a
> non-SMP kernel.

Have you tried using "noapic"?

> 
> Googling around, there seem to be plenty of reports of similar behaviour
> in 694X systems, but little in the way of definite solutions (with the
> possible exception of someone who claimed to have fixed it by lowering a
> voltage setting in their BIOS; my board's BIOS doesn't my give any
> control of that unfortunately).
> 
> Anyway, my question is this: is this chipset simply broken at the
> hardware level (and I should just resign myself to uniprocessing) or is
> there is some cunning combination of boot options and/or kernel compile
> flag gnosis which will let me SMP with confidence ?
> 
> Thanks for any advice
> Tim
>