Weird sequence of events with multiple processors seemingly dying

NF7-S mobo w/Mobile Athlon 2500 @ 2455Mhz (11x223)


My CPU temp has always appeared in negative temperatures so I naturally
assumed that the sensor was screwed up.

Needing an idea of what the temp. is, I bought a secondhand Digital Doc. I
managed to get one of the flat sensors wedged into the top of the heatsink,
fairly near the base. I always added 10 degrees to this when guesstimating
the cpu temp!

Wanting a more accurate measure, I decided to try and slide two flat sensors
PARTIALLY underneath the cpu whilst the lever was raised, then lower the
lever and have them wedged in. I removed my motherboard and installed them
so they weren't touching any pins.

When I'd put everything back together again, the PC booted up but the
monitor didn't come on. I realised I had a problem and instantly powered
off. I removed the motherboard and the sensors, then tested everything
again. This time it was ok. Before returning the motherboard to the case, I
decided to take a close look at the mobo-based sensor under the cpu. When I
looked closely at it, it seemed to be too far from the cpu itself. I bent it
upwards so that it would touch the cpu - not thinking that this could cause
any damage.

When I turned the PC back on, the fans started and the HDD's began to
spin-up but everything just cut out and stopped. The light on the mobo was
on and didn't do anything so I tried again - same thing happened. Somehow
forgetting that I'd made a significant change by moving the sensor, I tried
a 2600 athlon. Same problem. Next up a 2000 athlon... nope, nothing
happening.

I took my processors over to my other PC (PC#2) and quickly removed the
cover and first tried the mobile 2500. Exactly the same problem occured - it
switched off after a few seconds. This repeated itself with the next two
processors.

I was absolutely gutted. I couldn't believe I'd wrecked 3 cpu's in about 5
minutes.Amazingly, it was only now that I recalled having adjusted the
sensor on my NF7. I bent back the sensor and installed the cpu but the
problem was the same. Over the next 20 minutes I switched PSUs around, tried
different cables and even turned off major appliances in the hope that there
was some sort of overload going one. Out of nowhere, the idea came to cover
the sensor with something. The obvious material seemed to be a piece of an
anti-static bag . I cut a tiny square and covered the sensor. When I
switched the pc on with the mobile athlon...success! I tested the 2000
next - yay! Finally the 2600. That didn't work but I wasn't too bothered as
it doesn't have a place in any PC I own right now. It was only now that I
had connected up my PC speaker. All three produced a two-tone siren
(overheating or out of specification voltages?)which stopped on the
mobile2500 and 2000 but continued on the 2600 until I switched off.

Having found a solution, I bent the sensor back and made sure the
anti-static material was in place. The PC booted up fine and delivered a
real temp. reading at last. Before putting the mobo back in the case, I
again tested the 2000 in PC#2. Now, before all of this nonsense began, that
athlon 2000 had been running on PC#2 without problems. I put it back in #2
but it went back to the switching itself problem! How? Why? What??!?! There
isn't a sensor on PC#2! I hadn't adjusted anything! It seemingly copied it's
more impressive counterpart.

Once I'd got the mobo back in the case and upstairs, my NF7-S decided to
give nonsense voltages again. Although this was very frustrating, I'm more
than happy that it works at all!

As to nonsense voltages, you could get a bunch of the little red insulating
washers at a computer shop and put them on both sides of the motherboard at
each mounting point. Just in case it's shorting to ground.


--
Ed Light

Smiley :-/
MS Smiley :-\

Send spam to the FTC at

Thanks, robots.

Make sure the little bit of anti-static plastic doesn't melt! I dont know
what temp this would happen, but its only thin plastic!

"SpellmanXP" **** wrote in message
...
NF7-S mobo w/Mobile Athlon 2500 @ 2455Mhz (11x223)


My CPU temp has always appeared in negative temperatures so I naturally
assumed that the sensor was screwed up.

Needing an idea of what the temp. is, I bought a secondhand Digital Doc. I
managed to get one of the flat sensors wedged into the top of the
heatsink, fairly near the base. I always added 10 degrees to this when
guesstimating the cpu temp!

Wanting a more accurate measure, I decided to try and slide two flat
sensors PARTIALLY underneath the cpu whilst the lever was raised, then
lower the lever and have them wedged in. I removed my motherboard and
installed them so they weren't touching any pins.

When I'd put everything back together again, the PC booted up but the
monitor didn't come on. I realised I had a problem and instantly powered
off. I removed the motherboard and the sensors, then tested everything
again. This time it was ok. Before returning the motherboard to the case,
I decided to take a close look at the mobo-based sensor under the cpu.
When I looked closely at it, it seemed to be too far from the cpu itself.
I bent it upwards so that it would touch the cpu - not thinking that this
could cause any damage.

When I turned the PC back on, the fans started and the HDD's began to
spin-up but everything just cut out and stopped. The light on the mobo was
on and didn't do anything so I tried again - same thing happened. Somehow
forgetting that I'd made a significant change by moving the sensor, I
tried a 2600 athlon. Same problem. Next up a 2000 athlon... nope, nothing
happening.

I took my processors over to my other PC (PC#2) and quickly removed the
cover and first tried the mobile 2500. Exactly the same problem occured -
it switched off after a few seconds. This repeated itself with the next
two processors.

I was absolutely gutted. I couldn't believe I'd wrecked 3 cpu's in about 5
minutes.Amazingly, it was only now that I recalled having adjusted the
sensor on my NF7. I bent back the sensor and installed the cpu but the
problem was the same. Over the next 20 minutes I switched PSUs around,
tried different cables and even turned off major appliances in the hope
that there was some sort of overload going one. Out of nowhere, the idea
came to cover the sensor with something. The obvious material seemed to be
a piece of an anti-static bag . I cut a tiny square and covered the
sensor. When I switched the pc on with the mobile athlon...success! I
tested the 2000 next - yay! Finally the 2600. That didn't work but I
wasn't too bothered as it doesn't have a place in any PC I own right now.
It was only now that I had connected up my PC speaker. All three produced
a two-tone siren (overheating or out of specification voltages?)which
stopped on the mobile2500 and 2000 but continued on the 2600 until I
switched off.

Having found a solution, I bent the sensor back and made sure the
anti-static material was in place. The PC booted up fine and delivered a
real temp. reading at last. Before putting the mobo back in the case, I
again tested the 2000 in PC#2. Now, before all of this nonsense began,
that athlon 2000 had been running on PC#2 without problems. I put it back
in #2 but it went back to the switching itself problem! How? Why?
What??!?! There isn't a sensor on PC#2! I hadn't adjusted anything! It
seemingly copied it's more impressive counterpart.

Once I'd got the mobo back in the case and upstairs, my NF7-S decided to
give nonsense voltages again. Although this was very frustrating, I'm more
than happy that it works at all!

"Gareth Tuckwell" wrote in message
...
Make sure the little bit of anti-static plastic doesn't melt! I dont know
what temp this would happen, but its only thin plastic!



I wondered about this too!

I'm sure it won't be long before I make another attempt to fix the sensor,
so I'll probably replace it with "something better" - but what???

Make sure the little bit of anti-static plastic doesn't melt! I dont know
what temp this would happen, but its only thin plastic!

I wondered about this too!

I'm sure it won't be long before I make another attempt to fix the sensor,
so I'll probably replace it with "something better" - but what???

What about a bit of electrical insulating tape or even celotape? I don't
suppose either would melt, but I know nothing about their properties
regarding heat - anyone help out here - is celotape conductive? What temp
melts it?

Electrical tape is not conductive but celotape can be conductive and it
melts.
Try some thermal tape or strips like you get with a heat sink. It's not
suppose to conduct electricity.
You might check the motherboard connection where the thermal resistor
attaches, could be loose.
Sounds like a bad sensor (thermal resistor), is the MB still under warranty?
Don't forget to disable the thermal safety features in the BIOS they will
shut down the computer with a two tone siren if the temperature exceeds the
thresholds.

"Gareth Tuckwell" wrote in message
...
Make sure the little bit of anti-static plastic doesn't melt! I dont
know what temp this would happen, but its only thin plastic!

I wondered about this too!

I'm sure it won't be long before I make another attempt to fix the
sensor, so I'll probably replace it with "something better" - but what???

What about a bit of electrical insulating tape or even celotape? I don't
suppose either would melt, but I know nothing about their properties
regarding heat - anyone help out here - is celotape conductive? What temp
melts it?

maybe the liquid insulation stuff?


--
Ed Light

Smiley :-/
MS Smiley :-\

Send spam to the FTC at

Thanks, robots.