Perfectly working workstation suddenly fails to POST - thoughts please

[mikepro]

Hi all

I'm stumped as to why a machine built six years ago all of a sudden will not
even successfully complete the power on self test before loading the BIOS.

The pc itself had been in regular use (switch on once per day at least) and
the last boot-up request was into "Safe-mode" after shut down and restart
re-boot into normal mode and finally normal (start menu) shut-down.

That was the last time it booted up. I've gone through the process of
removing one component at a time - followed by testing of same components in
a "working" system. But no joy. The only thing I'm left thinking is - after
six years would the 5v battery need replacing..? I've no experience of
purchasing one never mind changing it!

Mind, a friend of mine says its not too tough...
Any thought or useful suggestions on the above?

Kind thanks in advance

 

[Chris Hill]

Hi all

I'm stumped as to why a machine built six years ago all of a sudden will not
even successfully complete the power on self test before loading the BIOS.

The pc itself had been in regular use (switch on once per day at least) and
the last boot-up request was into "Safe-mode" after shut down and restart
re-boot into normal mode and finally normal (start menu) shut-down.

That was the last time it booted up. I've gone through the process of
removing one component at a time - followed by testing of same components in
a "working" system. But no joy. The only thing I'm left thinking is - after
six years would the 5v battery need replacing..? I've no experience of
purchasing one never mind changing it!

Mind, a friend of mine says its not too tough...
Any thought or useful suggestions on the above?

Generally, a battery won't keep a machine from booting. I'd suggest
taking a careful look at the capacitors on the mainboard. They are
round things that look like little cans with a slash or an x in the
top. If any are bulging or leaking, you've found the problem. Six
years is pretty good out of a machine.

 

[kony]

Hi all

I'm stumped as to why a machine built six years ago all of a sudden will not
even successfully complete the power on self test before loading the BIOS.

What do you mean "before loading the bios"?
Do you mean, it goes into the bios settings menu?

If so, I'd wonder if the battery were dying. Otherwise a
general instability might be causing it to restart with
default values, could be a motherboard or psu instability.

The pc itself had been in regular use (switch on once per day at least) and
the last boot-up request was into "Safe-mode"

What is "boot-up request"?
Can you more clearly describe what you see, but we don't...

... after shut down and restart
re-boot into normal mode and finally normal (start menu) shut-down.

That was the last time it booted up. I've gone through the process of
removing one component at a time - followed by testing of same components in
a "working" system.

Which same components?
ALL of them?
Did you try running system with only bare essentials, IE-
cpu, video, 1 memory module, then adding the OS boot drive?
Also try underclocking it to the lowest FSB the board
supports, if possible. (for testing purposes only, not
regular use).

But no joy. The only thing I'm left thinking is - after
six years would the 5v battery need replacing..? I've no experience of
purchasing one never mind changing it!

3V battery, check the motherboard manual if you like but a
glance at the board should suffice. "Typically" it's a
CR2032 size, available at many drugstores/etc. (Or online,
but it costs about $1 so shipping charge is a large cost
overhead on such a part).

Mind, a friend of mine says its not too tough...

True, there's a little springy tab that holds the top edge
of the cell, just gently pull it back and the battery pops
out. The new cell just pushes in rather easily so long as
you can see what you're doing. Have the system AC power
disconnected while doing it.

 

[Rod Speed]

I'm stumped as to why a machine built six years ago
all of a sudden will not even successfully complete
the power on self test before loading the BIOS.

Anything that can die has to die sometime.

The pc itself had been in regular use (switch on once
per day at least) and the last boot-up request was into
"Safe-mode" after shut down and restart re-boot into
normal mode and finally normal (start menu) shut-down.

That was the last time it booted up. I've gone through the process
of removing one component at a time - followed by testing of same
components in a "working" system. But no joy.

Worth trying with nothing except a cpu, see if
it will beep complaining about the lack of ram.

The only thing I'm left thinking is - after six years would the 5v battery need
replacing..? I've no experience of purchasing one never mind changing it!

Wont produce that particular symptom.

Something has died.

Mind, a friend of mine says its not too tough...
Any thought or useful suggestions on the above?

Check for bad caps, those are the usually blue or black plastic
covered post like things sticking up vertically from the motherboard.
The tops should be flat. If any have bulged or are leaking, thats
a bad cap and the only viable approach is to replace the motherboard.

Could be a bad power supply too, and that may well be easier to try swapping.

Can also be a short to case, but the best test for that is to try
running the motherboard loose and see if it will complete the POST.
Not a great idea tho if you arent comfortable changing the battery.

 

[philo]

That was the last time it booted up. I've gone through the process of
removing one component at a time - followed by testing of same components
in
a "working" system. But no joy. The only thing I'm left thinking is -
after
six years would the 5v battery need replacing..? I've no experience of
purchasing one never mind changing it!

Mind, a friend of mine says its not too tough...
Any thought or useful suggestions on the above?

Though a dead battery will usually not prevent a machine from posting...
I have seen a few machines with a battery around 1.6 volts or so...that did
lockup the bios.

Since the machine is 6 years old...you might as well try a new battery
and reset the bios (the jumper is usually near the battery)

 

[mikepro]

"kony" wrote in message:

BIOS.

What do you mean "before loading the bios"?
Do you mean, it goes into the bios settings menu?

Yes, I should have been much more clearer I know...

You know that little "beep" you get from the system speaker to signify the
successful completion of the post? Well, its not reaching that far. That is
ultimatly the problem. So, nothing appears on the screen (yes, I've checked
the monitor with another system and its fine). I've also taken pretty much
everything but the suggestions about the 1.5v battery on the main board and
put into practice.

That kind of leaves me with only that left to try...
I'm determined to give it a go.

If so, I'd wonder if the battery were dying. Otherwise a
general instability might be causing it to restart with
default values, could be a motherboard or psu instability.

I don't think this is the case as such, but yes, the battery as you say
could be problem. Should I succeed at getting the system to post, then I
logically imagine - as nothing was changed to the BIOS, it would naturally
boot as it did before...?

 

[kony]

I don't think this is the case as such, but yes, the battery as you say
could be problem. Should I succeed at getting the system to post, then I
logically imagine - as nothing was changed to the BIOS, it would naturally
boot as it did before...?

No, there is no point speculating.

Focus on the problem- posting
Fix that
See if it boots
If not, fix that.

It might boot or might not, especially depending on the need
to set bios settings after a battery swap.

 

[mikepro]

in message:

Focus on the problem- posting
Fix that
See if it boots
If not, fix that.

It might boot or might not, especially depending on the need
to set bios settings after a battery swap.

Progress report:
Well, I replaced the 3v battery on the mboard - I'm still no closer to
getting the system to post. I spent the best part of this morning working on
it, checked the circuit and components of the board itself and nothing (that
looks obvious anyway) appears to have come loose or broken off...

The power supply seems fine imo, otherwise why would the drives light up,
heatsink and northbridge start spinning? So, I guess just replacing the main
board should do the trick! As all the upgradeable components are fine.

I'll give it one last go - probably next week now. Afterwhich, I'll put this
system to bed and perhaps consider building a new one in the future...
My thanks to all for posting advice.

Michael

 

[JAD]

in message:


Progress report:
Well, I replaced the 3v battery on the mboard - I'm still no closer to
getting the system to post. I spent the best part of this morning working on
it, checked the circuit and components of the board itself and nothing (that
looks obvious anyway) appears to have come loose or broken off...

The power supply seems fine imo, otherwise why would the drives light up,
heatsink and northbridge start spinning? So, I guess just replacing the main
board should do the trick! As all the upgradeable components are fine.

this is not a good way to determine the PSU's functionality, IMO its the
PSU.

 

[kony]

in message:


Progress report:
Well, I replaced the 3v battery on the mboard - I'm still no closer to
getting the system to post. I spent the best part of this morning working on
it, checked the circuit and components of the board itself and nothing (that
looks obvious anyway) appears to have come loose or broken off...

The power supply seems fine imo, otherwise why would the drives light up,
heatsink and northbridge start spinning? So, I guess just replacing the main
board should do the trick! As all the upgradeable components are fine.

A malfunctioning PSU can appear to power drives, fans, and
still be the problem. We can't know for sure, you might
take voltage readings but in some cases that won't even
reveal the problem, but substituting a known good (not just
new but demonstrated working with similar load) PSU might be
tried.

I'll give it one last go - probably next week now. Afterwhich, I'll put this
system to bed and perhaps consider building a new one in the future...
My thanks to all for posting advice.

Unless I overlooked it you never did tell us WHAT this
system is. Details are good. Maybe it won't help at this
point, or maybe if you had provided the details up front the
thread would have taken an entirely different tangent.

 

[mikepro]

in message

A malfunctioning PSU can appear to power drives, fans, and
still be the problem. We can't know for sure, you might
take voltage readings but in some cases that won't even
reveal the problem, but substituting a known good (not just
new but demonstrated working with similar load) PSU might be
tried.

Unless I overlooked it you never did tell us WHAT this
system is. Details are good. Maybe it won't help at this
point, or maybe if you had provided the details up front the
thread would have taken an entirely different tangent.

AMD 1Ghz
Abit KT7 - mboard
230 PSU
1x256, 2x128 unbranded ram
ASUS 64mb GeForce3
Creative 16v Sound
Trust 10/100 NIC
Maxtor 8.4G 5400 HD
40x CD-ROM unbranded
FDD

I think thats the lot...
Yes, I shall take your advice and change the PSU to see it thats works.
Otherwise I'll be stripping the system for parts.

Michael

 

[kony]

in message



AMD 1Ghz
Abit KT7 - mboard
230 PSU
1x256, 2x128 unbranded ram
ASUS 64mb GeForce3
Creative 16v Sound
Trust 10/100 NIC
Maxtor 8.4G 5400 HD
40x CD-ROM unbranded
FDD

I think thats the lot...
Yes, I shall take your advice and change the PSU to see it thats works.
Otherwise I'll be stripping the system for parts.

230W PSU is marginal for that system, after adding the GF3
it was better to target about 300W PSU or a minimum of 180W
(better 200W or more) of combined 3V+5V power rating.

if it's a generic PSU of questionable rating accuracy, even
more likely to be a problem. That doesn't necessarily mean
the PSU is the problem or hasn't damaged something else
though, when examination and testing reveals nothing the
only alternative left is to start swapping known-good parts
or give up.