Bad A7N8X - ?

[Vince]

Lemme know what you think:

The patient: A7N8X Deluxe mobo, rev. 2.00. About 2 years
old, flashed with latest (1008) bios.

Will boot one time only, after clearing CMOS, to 11x100 MHz.
Can get into setup just fine, or boot to MEMTEST86, which
reports a good, clean memory test.

Then, if I go into setup and save new settings (even if I don't
actually change anything), a second boot ALWAYS results in
the voice message "system failed memory test". If however,
I go into setup and choose to exit without save, it WILL reboot
to the default, 11x100MHz mode.

I have swapped out two known good Athlon XP 2500 CPU's,
and two known good pairs of PC3200 memory, even tried it
with a single stick (non-DDR mode), as well as two different
video cards.

I replaced the CR2032 battery with a fresh one, same result.

What's your take on this?

 

[Ed]

Lemme know what you think:

The patient: A7N8X Deluxe mobo, rev. 2.00. About 2 years
old, flashed with latest (1008) bios.

Will boot one time only, after clearing CMOS, to 11x100 MHz.
Can get into setup just fine, or boot to MEMTEST86, which
reports a good, clean memory test.

Then, if I go into setup and save new settings (even if I don't
actually change anything), a second boot ALWAYS results in
the voice message "system failed memory test". If however,
I go into setup and choose to exit without save, it WILL reboot
to the default, 11x100MHz mode.

I have swapped out two known good Athlon XP 2500 CPU's,
and two known good pairs of PC3200 memory, even tried it
with a single stick (non-DDR mode), as well as two different
video cards.

I replaced the CR2032 battery with a fresh one, same result.

What's your take on this?

Have you tried to flash it back to the BIOS that was working previously?

Ed

 

[Vince]

Have you tried to flash it back to the BIOS that was working previously?

Ed

When the trouble started, it was running on v. 1007. I updated
to 1008 in an attempt to fix the problem, but it made no difference.

 

[S.Heenan]

Lemme know what you think:

The patient: A7N8X Deluxe mobo, rev. 2.00. About 2 years
old, flashed with latest (1008) bios.

Will boot one time only, after clearing CMOS, to 11x100 MHz.
Can get into setup just fine, or boot to MEMTEST86, which
reports a good, clean memory test.

Then, if I go into setup and save new settings (even if I don't
actually change anything), a second boot ALWAYS results in
the voice message "system failed memory test". If however,
I go into setup and choose to exit without save, it WILL reboot
to the default, 11x100MHz mode.

I have swapped out two known good Athlon XP 2500 CPU's,
and two known good pairs of PC3200 memory, even tried it
with a single stick (non-DDR mode), as well as two different
video cards.

I replaced the CR2032 battery with a fresh one, same result.

What's your take on this?

How did you flash the BIOS, with the Win32 utility or with a DOS boot disk ?

 

[Dave McCaleb]

Hi,
Have you tried disabling the mem test in the BIOS? It won't correct the
problem, but maybe it will skip it so you can work with the computer.
Dave

 

[Beemer Biker]

Lemme know what you think:

The patient: A7N8X Deluxe mobo, rev. 2.00. About 2 years
old, flashed with latest (1008) bios.

Will boot one time only, after clearing CMOS, to 11x100 MHz.
Can get into setup just fine, or boot to MEMTEST86, which
reports a good, clean memory test.

Then, if I go into setup and save new settings (even if I don't
actually change anything), a second boot ALWAYS results in
the voice message "system failed memory test". If however,
I go into setup and choose to exit without save, it WILL reboot
to the default, 11x100MHz mode.

I have swapped out two known good Athlon XP 2500 CPU's,
and two known good pairs of PC3200 memory, even tried it
with a single stick (non-DDR mode), as well as two different
video cards.

I replaced the CR2032 battery with a fresh one, same result.

What's your take on this?

Pull board from case, remove all adapter & cables except the video board.
Pull the front panel cables, ribbon cables, usb, etc to where you have to
short together the power jumper to turn on the power. Only the ATX and AUX
should be connected Remove the 3 cable fan connectors even the one on the
CPU. It is possible the fan can induce noise onto the motherboard and you
might have a ground loop problem. Keep motherboard on an insulated surface
and see if you can repeat the problem. As long as you dont take too long
the cpu will not overheat. Try swapping the power supply. If all this
fails then sell it on ebay.
While you got the motherboard out, look at the top of the capacitors for one
that is bulging. I have replaced about 40 caps on various alton and
pcchips. I did have one cap blow on an asus A7N8X-DLX but the motherboard
actually worked without it.

...good luck..

 

[Vince]

Beemer & everyone -

Thanks for the suggestions. I removed the mobo and hooked up
everything one component at a time, like Beemer suggested. So
far, so good. Then I put the mobo back in the case. One at a time,
I hooked up the cables, cd-rom, HD, floppy. Still perfect. Ran
memtest86 again, came up clean, so I installed XP, and everything's
rock solid now, 24 hours running Prime95 without a hitch and
rebooting every now and then without any trouble like before.

Just a ghost in the machine, I guess....

Thanks for your help!

 

[Beemer Biker]

Beemer & everyone -

Thanks for the suggestions. I removed the mobo and hooked up
everything one component at a time, like Beemer suggested. So
far, so good. Then I put the mobo back in the case. One at a time,
I hooked up the cables, cd-rom, HD, floppy. Still perfect. Ran
memtest86 again, came up clean, so I installed XP, and everything's
rock solid now, 24 hours running Prime95 without a hitch and
rebooting every now and then without any trouble like before.

Just a ghost in the machine, I guess....

Thanks for your help!

Thanks for letting us know you got it running. Some people never report
back one way or another and it is nice to know the outcome of problems like
the one you had.

 

[Paul D. Motzenbecker, Jr.]

Beemer and Vince,
Greetings and hallucinations from just north of Fantasy Land (Washington,
DC)!
Beemer was giving standard and quite good advice on how to troubleshoot a
motherboard. Remove all of the accessories (to be technical the case is an
accessory) and then add things back in one at a time. It is a good trick to
remember.
Peace,
Paul