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Old October 12th 04, 03:39 AM
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"kony" wrote in message
...
Followups-To alt.comp.hardware

A7N8X Motherboard Low Temperature Sensitivity, CMOS Checksum
Error



SHORT VERSION:

If room ambient temp drops below 25C, system is so
instable it can't even complete a POST. If system is
running when room temp drops, it then starts to act erratic
(odd Explorer pauses and Prime95 errors), powering off then
back on a dozen seconds later, fails resulting in only
""CMOS Checksum Error" and automatically booting to floppy,
running awdflash.

Once ambient temp rises to 32-24C, system always POSTS
and runs fine. In-between these temps, failure to get
beyond "CMOS Checksum Error" and errors in Windows, go up in
frequency as temp drops. Multiple troubleshooting attempts
have been made (Clear CMOS, BIOS flash, swap hardware,
remount board in case, strip down system, etc), problem
appears isolated to motherboard itself. Different BIOS,
bios defaults, etc, have been tried. System is not
overclocked.

What are the potential cause(s) and the best methods to
check these?


snip

Kony

If you've narrowed the problem to the motherboard by substituting all other
components, then the 'freeze spray' technique would appear to be about the
only way of finding which component it is.
I had a kitset computer many years ago that did exactly what you describe
(erratic within a temperature range) The can of 'Freeze' found the culprit
in less than 10 minutes. (Z80 CPU as it happens)

The only 'concern' with using Freeze spray is when the humidity is high
enough to cause condensation, shorting high impedance lines out. (High
impedance = low power CMOS circuitry these days)

Just do it in methodically, the boards U/S anyway so you've nothing to
loose.

Cheers
Paul.