How to diagnose PC with black screen?
 

PC #1
Computer switches on, but screen remains black, no
messages, no beeps. Tried the hard disk on another
machine and it worked. Tried the network card on
another machine and it worked. Tried 32MB DIMM
memory module on another machine and it appears
to be dead. Has AMD 500 MHz CPU and GigaByte main
board.

Is it possible for a RAM memory module to be erased
or is it likely destroyed due to an electrical
problem?

Did not try the flash BIOS chip or PCI graphics card
on another machine, so I don't know if they have been
erased or destroyed. Any ideas?


PC #2
Very similar symptoms to PC #1. Computer worked fine
last time I used it. Now, when I switch it on, it
switches itself off (some sort of short?). When I
switch it on again, it stays on, but the screen
remains black, no messages, no beeps. Has on-board
ATI graphics chip, ASUS main board and Pentium 2
166 MHz CPU. Any ideas?

In the first PC, do you get beeps if you take out the ram completely ? (of
course you won't get any video, but it should beep).

Pull every card and device out that you can, then reseat video card and see
what happens.. (I only say put video card back in so you can see if you get
a POST).

Also, try clearing the cmos on both machines..


Regards,
Chris

Try re-installing the chip it may not be seated correcly


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Procedure is quite simple, straight forward, involves tools
that are inexpensive and commonly sold in major stores, AND is
not about hunting.

Start by confirming the power supply system this is PSU,
motherboard controller, and power switch. Does not matter if
machine turns on, then off. Reason for that failure is also
found in this simple procedu "Computer doesnt start at all"
in alt.comp.hardware on 10 Jan 2004 at
http://tinyurl.com/2t69q or

"I think my power supply is dead" in alt.comp.hardware on 5
Feb 2004 at http://tinyurl.com/yvbw9

Until you have verified this part, then all other testing
and speculation is simply time wasting.


Little Ghost wrote:
PC #1
Computer switches on, but screen remains black, no
messages, no beeps. Tried the hard disk on another
machine and it worked. Tried the network card on
another machine and it worked. Tried 32MB DIMM
memory module on another machine and it appears
to be dead. Has AMD 500 MHz CPU and GigaByte main
board.

Is it possible for a RAM memory module to be erased
or is it likely destroyed due to an electrical
problem?

Did not try the flash BIOS chip or PCI graphics card
on another machine, so I don't know if they have been
erased or destroyed. Any ideas?

PC #2
Very similar symptoms to PC #1. Computer worked fine
last time I used it. Now, when I switch it on, it
switches itself off (some sort of short?). When I
switch it on again, it stays on, but the screen
remains black, no messages, no beeps. Has on-board
ATI graphics chip, ASUS main board and Pentium 2
166 MHz CPU. Any ideas?

w_tom wrote:

Little Ghost wrote:

Computer switches on, but screen remains black, no
messages, no beeps. Tried the hard disk on another
machine and it worked. Tried the network card on
another machine and it worked. Tried 32MB DIMM
memory module on another machine and it appears
to be dead. Has AMD 500 MHz CPU and GigaByte main
board.

Procedure is quite simple, straight forward, involves tools
that are inexpensive and commonly sold in major stores, AND is
not about hunting.

snipped

Thanks for all responses!
Ok, I didn't know about using a multimeter. I agree that it
makes sense to test with one. I also did not know about
removing the plug from the wall.

The situation so far is this (before latest information):

The computer boots from diskette and keyboard responds,
but screen is black. No beeps, no messages. If monitor
is disconnected, message appears on screen advising to
check connection. When I connect the monitor I can hear
that there is a connection being made. I tried two
different PCI graphics cards, but screen remained black.

Removing RAM memory causes beeps.
I reset the motherboard via jumper as per instructions
in GigaByte manual. I also removed the battery and put
it back. I will get a multimeter ASAP;in the meantime,
are these symptoms recognizable to anyone?

The situation so far is this (before latest information):

The computer boots from diskette and keyboard responds,
but screen is black. No beeps, no messages. If monitor
is disconnected, message appears on screen advising to
check connection. When I connect the monitor I can hear
that there is a connection being made. I tried two
different PCI graphics cards, but screen remained black.

The board doesn't have AGP or onboard video ? (I have not seen a board that
doesn't offer one of the two since socket7)
If the board has AGP and you are using PCI, it's very likely it's defaulting
to AGP as primary display, hence you get nothing.

I had the exact problem you describe on an old PII board.. PCI card and no
video.. turned out there was onboard video, just no header (plug) attached
to the board for it.. pulled the cmos battery, left it a while and
replaced.. finally it decided to use the PCI card as the default.. (though
once I got a POST, I had to enter bios and change primary display to PCI, or
else loading default settings brought the problem back).

One other machine I also has this problem with.. this one didn't have AGP or
onboard as it was an old Pentium 1 (socket7) board.. I pulled the battery
and put it back after a while.. nothing.. tried clearing with the jumper..
nothing.. out of interest I removed the clear cmos jumper entirely.. (so it
was neither on reset nor normal) and to my surprise it worked.. however
when I replaced the jumper the problem returned... in the end I put a new
cmos battery in it, put the jumper to the normal position again.. and it's
worked fine ever since ! (if anyone can explain this, please do!!)

Regards,
Chris