Re: memtest86 reboots

On Thu, Jun 24, 2004 at 02:32:23AM -0400, D. Hugh Redelmeier wrote:
> I have two new Athlon 64-based computers.  I'm having an odd problem with
> KNOPPIX on both.
> 
> To test the memory, I tried to run memtest from the KNOPPIX 3.4 CD's
> boot: prompt.  As soon as it starts to run memtest, the system reboots.
> I wonder what is wrong?
> 
> I have no trouble running memtest from the KNOPPIX boot prompt on
> another machine (happens to be an IBM a20p notebook).  It therefore
> seems unlikely that the CD is bad.
> 
> This happens on both Athlon 64 machines (they are pretty similar HP
> machines).  So the problem must be generic to this model rather than
> being a problem with a specific machine.

This may be, unfortunately I have no such computer for testing.

memtest86 is a generic program for memory checks, and does not use a
linux kernel or any kind of hardware detection, so it may be written
just with an assembler instruction set that is not capable of probing
64bit CPUs yet. On the other hand, maybe you just need a BIOS update for
your board in order to add the 32bit compatibility mode (which was not,
or wrongly, implemented in the first Athlon64 boards).

> memtest works when it is run from a memtest boot floppy (only one of
> the Athlon 64 machines has a floppy drive).  So the problem is not in
> memtest itself.

Could be a different version. Or have you copied memtest86 directly from
the CD to a floppy disk?

> The BIOS on these Athlon 64 machines is not the latest.  I cannot
> update it because HP only provides a way of flashing from Windows XP.
> I don't have Windows XP.

Hmm... Technically, in my opinion, this would be a warranty case, so the
vendor would have the responsibility to fix the "error" (old/broken
BIOS) somehow, rather than you having to do this yourself. Or, you just
return the board at the shop where you bought it, and get a new one with
an updated BIOS.

Regards
-Klaus Knopper