CPU Failure?? - using a K7T266 Pro2-U M'board

[Scooter9999]

After doing my weekly C Drive Defrag (Win XP Pro) I tried to do a reboot but
everyting came to a screeming halt!

No Bios messages, can't even get into the Bios Screen, no attempt to boot
from A Drive.

When I checked the D-Led, all 4 diodes are red which indicates faulty
CPU!!!!

Checked CPU and cooling fan working perfectly - no sign of overheating

Checked power supply, all voltages look fine

---------

My questions are:

1. Did the CPU really die on its own?
How usual is that?

However, if it did then I should just be able to replace the CPU and
everything should be fine

BUT

2. Could the motherboard have failed and blown the CPU?
Its my understanding that M'Boards fail far more frequenly than CPUs

If it is M'board related then just replacing the CPU will be no good and
will probably fry the new CPU! This scenario would require me to replace
BOTH the CPU and the M'Board which in my experience would probably require
me to completely reinstall WinXP and all my other SW!!!!

--------

I'm desperately hoping the its only the CPU that has failed and that the
D-Led lights are totally accurate in their diagnosis.

What do you think scenario 1 or 2 and why?

All comments welcome

Scooter

AMD 1600 CPU
MSI K7T266 Pro2-U M'board
512Mb Ram
Raedon 8500 Video
WinXP Pro
etc

 

[kony]

After doing my weekly C Drive Defrag (Win XP Pro) I tried to do a reboot but
everyting came to a screeming halt!

So you definitely didn't power off the system, just a warm
reset/restart?

No Bios messages, can't even get into the Bios Screen, no attempt to boot
from A Drive.

AT that point, I would've opened up the case, inspected the
motherboard capacitors, wiring, smelled the power supply for a burnt
smell, then tried powering on the system while watching all the fans.
If they're turning, I'd power off, disconnect from AC, and clear the
CMOS.

When I checked the D-Led, all 4 diodes are red which indicates faulty
CPU!!!!

Err, maybe it's accurate, but even so it doesn't mean the CPU is dead.
All that really means is that the POST stopped at that point, not
necessarily that the CPU is damaged. On the contrary, if the heatsink
was properly installed and the fan still works it'd be more likely
that the motherboard is dead or dying. Something as simple as setting
a multiplier that puts the CPU out of it's operating capabilities
would probably also produce that too, if somehow the CMOS got reset
and you'd fiddled with the multipliers on the CPU it might be trying
to run at the wrong speed. If not then clearing the CMOS as I
suggested above might help.

At one point I did have an MSI K7T Pro 2 that used that diagnostic
LED thingy, though I must admit I kept forgetting that I even had it,
so I didn't notice it's lights very often.

Checked CPU and cooling fan working perfectly - no sign of overheating
Checked power supply, all voltages look fine

---------

My questions are:

1. Did the CPU really die on its own?
How usual is that?

Extremely unusual unless the heatsink falls off or the motherboard has
a significant failure. As I wrote above the CPU is most likley fine,
might've be killed by the motherboard, a massive power surge or
who-knows-what, but most often the CPU works when there's no obvious
sign why it would've failed. You could be that really unlucky person
who had their CPU die, but for now I'd look elsewhere for the problem
and assume the CPU is fine until further evidence condemns it.

However, if it did then I should just be able to replace the CPU and
everything should be fine

It'd really help a lot to have another system handy, to swap parts
in/out. The best test might be pulling all your non-essential parts,
leaving in only one memory module, CPU, heatsink/fan, and video card,
removing all drives, keyboard, mouse, aux fans, etc, etc, THEN see if
it'll post (after clearing CMOS). If it still won't POST you might
pull the video card and inspect it, try a different one if there's
another vidcard available, but my first guess would be the
motherboard.

BUT

2. Could the motherboard have failed and blown the CPU?
Its my understanding that M'Boards fail far more frequenly than CPUs

Yes, motherboards do fail FAR more frequently, especially if they have
defective caps or on any semi-modern system running an Athlon, Duron,
P4, etc, CPU that uses a lot of energy and creates a lot of heat.

Try plugging your current CPU into another known working motherboard.
Or if you see vented/domed/leaky/etc capacitors on your motherboard
then pull it, decide whether to replace or repair.

If it is M'board related then just replacing the CPU will be no good and
will probably fry the new CPU!

The odds are that the CPU is ok. It might be dead but usually just
the motherboard goes. "Usually" means nothing to those UNusual cases,
but you have to start somewhere so ...

This scenario would require me to replace
BOTH the CPU and the M'Board which in my experience would probably require
me to completely reinstall WinXP and all my other SW!!!!

I'd boot from the CD and do a repair install. Or you could hunt down
the same motherboard and use same bios version. Those boards ought to
be pretty reasonably priced by now, maybe $30-50 if you can find one.
Although, if it won't take too long to reinstall everything you might
consider getting a good new board, then the NEXT time you want to
upgrade you'll just need new memory and CPU, and at that point you
wouldn't need to reinstall everything again.

I'm desperately hoping the its only the CPU that has failed and that the
D-Led lights are totally accurate in their diagnosis.

What do you think scenario 1 or 2 and why?

All comments welcome

Scooter

AMD 1600 CPU
MSI K7T266 Pro2-U M'board
512Mb Ram
Raedon 8500 Video
WinXP Pro
etc

The CPU is probably fine. If you can borrow a system, use someone
elses, or send both the motherboard and CPU to someone so they can
test them, you'd have a better idea.

I forget if there's a 100/133 FSB jumper on that board, but if there
is, you might also try moving it to 100MHz FSB for testing purposes.

Also if all else fails unplug the power supply for a few mintues, open
'er up and inspect internally, which is also a good time to clean the
dust out, lube fan(s) if they're sleeve-bearing type, etc.

Dave

 

[kony]

How do you clear the CMOS if there is no sign of BIOS activity on powerup?

It's cleared, or perhaps "reset" is a better word to use, with the
jumper. On my board this jumper was about 3cm to the right of the
Southbridge, right below the EEPROM (BIOS chip). If for some odd
reason they didn't include the physical jumper you could instead just
unplug the power supply from AC and pull the battery for 10 minutes.

The question for me is - what's the best strategy for getting things going?

1) Clear CMOS via the jumper, try powering on.

2) Strip system down to bare essentials (CPU, heatsink/fan, 1 memory
module, video card) NOTHING else connected to motherboard or power
supply (except perhaps the power switch connector) , then try powering
on again. _IF_ it's the power supply it can be helpful to unplug from
AC for anywhere from a few seconds to a few minutes, then plug back in
and immediately try to POST. Also if it won't post, you might leave
it sitting there for a few minutes, "running".

Can we assume this system was working for a fair amount of time with
no configuration changes or work inside the case just prior to the
problem?

AND

How can I minimise the chance of having to do a complete Windows XP rebuild

You can have it try to repair itself, which isn't TOO painful, but the
most painless way, if the motherboard needs replaced, might be
replacemement with the same motherboard, or "probably" the non-RAID
version would work too. In some cases changing the BIOS will even
preset windows with an excuse to re-plug-n-play hardware, so
replicating the original motherboard as nearly as possible would also
include the same BIOS version, but I don't think it likely that it's
necessary.


Dave