Tech help please? pc drives/fans, etc. run but no boot, no display

  • Thread starter Thread starter Sailor
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Sailor

Hello, I was recently using a computer when suddenly the video shutdown...
the drives and the fan were still running. I rebooted and everything spins
up but there were no beeps and no video.. not even the bios info that comes
up during boot. First I thought it was a video problem so I tried a
different video card, tried different slots, tested the monitor on a
different system, etc.

When I realized I wasn't even getting the usual beep, I figured out it was
a little deeper than a video card prob.

What I was wondering if the problem could be the memory (it's an old
computer with 72 pin edo ram), or the motherboard. Someone told me that if
it was the memory, it would probably still beep.

Anyway, any advice or opinion is appreciated. The computer is not my main
system but It's part of my home network and it comes in handy.

Thanks in advnace!
Sailor
 
Sailor said:
Hello, I was recently using a computer when suddenly the video shutdown...
the drives and the fan were still running. I rebooted and everything spins
up but there were no beeps and no video.. not even the bios info that comes
up during boot. First I thought it was a video problem so I tried a
different video card, tried different slots, tested the monitor on a
different system, etc.

When I realized I wasn't even getting the usual beep, I figured out it was
a little deeper than a video card prob.

What I was wondering if the problem could be the memory (it's an old
computer with 72 pin edo ram), or the motherboard. Someone told me that if
it was the memory, it would probably still beep.

Anyway, any advice or opinion is appreciated. The computer is not my main
system but It's part of my home network and it comes in handy.

Thanks in advnace!
Sailor
Click to expand...

Visually inspect the capacitors (tall cylinders with plastic
sleeving on the outside). The tops are supposed to be flat.
When the cap is about to fail, it will bulge on top. Sometimes
you'll see a brown stain underneath the capacitor, when
the electrolyte leaks out and dries onto the motherboard.
If you have failing caps, if they are allowed to degrade
further, eventually they overload the Vcore regulator, and
can cause damage to the switching MOSFETs or to the inductors
(donut with wire on it). It is much easier to find
replacement caps, than to find exact replacement MOSFETs
or inductors. (motherboardrepair.com fixes caps)

Other than that, the next thing to suspect, would be that a
single output on the supply is bad, while the others are
still providing juice. But that doesn't seem too likely.

A failure to beep, means the processor is not able to
execute any BIOS code. And a lack of power to the processor,
caused by bad caps, is one possibility. At the very least,
have a look around inside the case, and see whats up.

Paul
 
(e-mail address removed) (Paul) wrote in
Visually inspect the capacitors (tall cylinders with plastic
sleeving on the outside). The tops are supposed to be flat.
When the cap is about to fail, it will bulge on top. Sometimes
you'll see a brown stain underneath the capacitor, when
the electrolyte leaks out and dries onto the motherboard.
If you have failing caps, if they are allowed to degrade
further, eventually they overload the Vcore regulator, and
can cause damage to the switching MOSFETs or to the inductors
(donut with wire on it). It is much easier to find
replacement caps, than to find exact replacement MOSFETs
or inductors. (motherboardrepair.com fixes caps)

Other than that, the next thing to suspect, would be that a
single output on the supply is bad, while the others are
still providing juice. But that doesn't seem too likely.

A failure to beep, means the processor is not able to
execute any BIOS code. And a lack of power to the processor,
caused by bad caps, is one possibility. At the very least,
have a look around inside the case, and see whats up.

Paul
Click to expand...

Thanks for your reply. I will look over the caps. I forgot to mention that
during the course of trying to figure this whole thing out, it DID boot up
once and stayed on for about 10 minutes before stopping again, and another
time it ALMOST booted (got the bios info screen), then failed.. since then,
nothing... but that could definitely be a sign of a bad capacitor as it was
still storing charge.

It's funny that you mentioned the power supply. I considered that too and
could easily test that with a multi tester. The processor itself does not
have a fan, only a heat sink... and even if I leave it on for a bit it
doesn't warm up at all... soo, maybe not getting power, maybe the processor
itself like darklight said.

Anyway, thanks again for your help
sailor
 
my guess would be the cpu text cpu in another pc
Click to expand...

Thanks darklight, that's a good idea... actually, I don't have another pc
to try it in... but I think I have another processor that I could try in
this one.. if it works, then it is the processor..

thanks again,
sailor
 
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