Hardware help: monitor suddenly stopped getting a signal from PC

**doodab** · 20 August 2012, 17:25

You could try a different graphics card. You can also listen for the POST beeps and see what they have to say assuming there are any.

**VectraMan** · 20 August 2012, 18:06

Presumably you're not getting the boot text either? I.e. if you're seeing the normal boot up, and then the monitor switches off as it enter Windows, it's probably down to a driver update.

If you're seeing nothing at all, you should probably just buy a new graphics card.

**petergriffin** · 20 August 2012, 18:34

How do you know it's not the CPU that is fcuked up?

Was the BIOS configured so that it could boot from a CD/DVD bypassing the hard drive? Can you or somebody else get one of those Linux live cd's that load a ssh server automatically (I can't remember which one does, I'm pretty sure the Slackware installation CD comes with one, I can investigate if you want).

Once the CD/DVD is fully booted, you can try to ssh into the faulty PC from another PC (with Putty) and troubleshoot the PC (dmesg). See, one good thing of Linux is that it doesn't need a graphics card to boot.

**ChimpMaster** · 20 August 2012, 18:48

Originally posted by doodab View Post

You could try a different graphics card. You can also listen for the POST beeps and see what they have to say assuming there are any.

I don't have any other graphics cards to hand. I could buy a replacement for around £50, but I'm beginning t doubt it's the graphics card that is at fault here (see below)

Originally posted by VectraMan View Post

Presumably you're not getting the boot text either? I.e. if you're seeing the normal boot up, and then the monitor switches off as it enter Windows, it's probably down to a driver update.

If you're seeing nothing at all, you should probably just buy a new graphics card.

I'm seeing nothing - literally it's as though the cable has been pulled out. It would be nice if there was another way to see what the PC was doing during boot i.e. without having to rely on the graphics card. I was thinking of getting a graphics card but I reckon somethng else is wrong: I put the sound up and turned on the PC and there were no beeps during bootup and no Windows startup sound. I was thinking that I would hear something - if the PC was booting correctly.

Originally posted by petergriffin View Post

How do you know it's not the CPU that is fcuked up?

Was the BIOS configured so that it could boot from a CD/DVD bypassing the hard drive? Can you or somebody else get one of those Linux live cd's that load a ssh server automatically (I can't remember which one does, I'm pretty sure the Slackware installation CD comes with one, I can investigate if you want).

Once the CD/DVD is fully booted, you can try to ssh into the faulty PC from another PC (with Putty) and troubleshoot the PC (dmesg). See, one good thing of Linux is that it doesn't need a graphics card to boot.

The BIOS is configured to boot from CD/DVD first but unfortunately I wouldn't even know where to begin with the Linux SSH stuff! Everything looks like it's running OK when I turn the PC on, but the lack of beeps and Windows startup sounds indicates to me that it is something other than the graphics card?

I'm thinking I might have to trash the PC... or is there soe way of working out which component is causing the problem?

EDIT: if the CPU is trashed, is this easy/cheap to replace?

**chef** · 21 August 2012, 06:27

So trying to understand the situation, could you work through the list and confirm or add any extra info to each point below

- is the computer plugged in and the plug switch on?
- your pc normally has working speakers attached and you do normally hear sound during pc startup I.we a single beep just after powering on and the windows jingle.
- you power on the pc and you can confirm it gets power? I.e light on motherboard lights up? and both case fan(s) and cpu fan start moving.
- do u hear any beeps? Many motherboards give a single beep after completing the basic POST test, I.e just after booting up but before starting windows.
- you do not hear the windows startup sound so we can assume that it does not get that far. Correct?
- the monitor and cable works as you have tried it connected to your laptop.
- does your motherboard have on board graphics? Most modern motherboards do, remove the graphics card, plug the monitor into the graphics output from the motherboard and try booting up without the graphics card.
- what is the make/ model of the graphics card?
- what is the make / model of the motherboard?
- are all the cables plugged in securely? No chance that the cat, the baby, the cleaner has unseated them or accidentally turned the main power supply switch off at the back of the machine?
- have u changed the RAM recently? Do u have any old spare ram that will work in the motherboard? Can u remove the ram, remove any dust and replace it and try again.
- is it a self build pc or bought? If bought what make/ model.

if u get no beeps, nothing when the pc turns on but you are getting power to it then my guess is that it is RAM or motherboard issues. No power then it's the psu , if your getting beeps then i think we can work out the problem. Single beep, windows jingle etc. all occurs then its graphics card or driver issues.

**administrator** · 21 August 2012, 08:14

If no onboard graphics adaptor on the mobo to test (I know, always worth checking though

) then if you have a PC World go an get a cheap £30 card, take it home, unpack it carefully, try it and then take it back and ask for a refund. "It was for my son / dad / wife and they already picked one up, I would like a refund please." Has to be the cheapest option for testing!

Just saw chef suggesting the onboard graphics in the last post - most mobo's have them so worth a check.

**doodab** · 21 August 2012, 08:19

Bear in mind that POST diagnostic beeps come from the old fashioned speaker that plugs into the motherboard, not the ones attached to the sound card, so if you don't have that attached or your case doesn't have one you won't hear them anyway. You can get cards that plug into PCI slots and give you a hex code as well, these aren't that expensive on eBay.

4 Digit PC ISA PCI Analyzer Diagnostic Test Post Card | eBay

The other way to diagnose which component is defective is to either try each part in turn in a known good machine or swap them out until you find the broken one. This is where being a geek with a lot of computers comes in handy.

**ChimpMaster** · 21 August 2012, 08:37

Originally posted by chef View Post

So trying to understand the situation, could you work through the list and confirm or add any extra info to each point below

- is the computer plugged in and the plug switch on?
Yep
- your pc normally has working speakers attached and you do normally hear sound during pc startup I.we a single beep just after powering on and the windows jingle.
No beeps at all. No Jingle, nada.
- you power on the pc and you can confirm it gets power? I.e light on motherboard lights up? and both case fan(s) and cpu fan start moving.
Yes the PC appears to be powering up correctly and all fans running. I can't see any lights in particular, I've not noticed any before (or perhaps they're drowned out by the blue neon lights in the tower!)
- do u hear any beeps? Many motherboards give a single beep after completing the basic POST test, I.e just after booting up but before starting windows.
No beeps at all
- you do not hear the windows startup sound so we can assume that it does not get that far. Correct?
That's correct, I'm quite sure it's not getting to Windows due to the lack of any jingle.
- the monitor and cable works as you have tried it connected to your laptop.
Yes the monitor/cable work when connected to my laptop
- does your motherboard have on board graphics? Most modern motherboards do, remove the graphics card, plug the monitor into the graphics output from the motherboard and try booting up without the graphics card.
I was hoping the motherboard had onboard graphics but it doesn't. Model is GA-945P-S3.
- what is the make/ model of the graphics card?
NVIDIA 8600GT 256MB
- what is the make / model of the motherboard?
Model is GA-945P-S3.
- are all the cables plugged in securely? No chance that the cat, the baby, the cleaner has unseated them or accidentally turned the main power supply switch off at the back of the machine?
Checked all this yesterday and it's all OK.
- have u changed the RAM recently? Do u have any old spare ram that will work in the motherboard? Can u remove the ram, remove any dust and replace it and try again.
Not added/changed in a long time. Will try cleaning when home tonight.
- is it a self build pc or bought? If bought what make/ model.
It was custom built by a small retailer for me. So all the parts are individual.

-if u get no beeps, nothing when the pc turns on but you are getting power to it then my guess is that it is RAM or motherboard issues. No power then it's the psu , if your getting beeps then i think we can work out the problem. Single beep, windows jingle etc. all occurs then its graphics card or driver issues.

I agree with your last comment. It's frustrating because there's no monitor output to allow me to work out what's going wrong. I've had problems with this PC in the past and have been able to solve everything because I've been able to at least get into Safe Mode, but this time it's just so difficult to see what's wrong!

I'll check the RAM tonight (though I have 4 x 1Gb sticks, so even if one blows then the others would be OK right?).

How can I check the motherboard?

How do I know if it's the CPU?

**chef** · 21 August 2012, 09:11

after searching google for "GA-945P-S3 does not power on"

the top answer is this thread

Exact same symptoms as you have, solution that worked for them is to replace the CMOS battery, the manual for the motherboard shows you where the battery is located. Remove it and replace it. Cheapest option to test first IMO. If someone knows of a standard CMOS battery type on here then you could grab one during lunch and test when you get home tonight. Unfortunately I have no idea of the Battery Type or even if there is such a thing as a standard motherboard battery type, it look slike an old watch battery is all I know.

Hardware help: monitor suddenly stopped getting a signal from PC