PC wont boot - no signal to monitor!

pdrnsf

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Jan 7, 2007
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Hi,

I`ve had my pc running fine for at least 3 years now. It got moved around a bit the other day while decorating and now it wont work. Since moving it back it booted fine the first time but after that I receive no signal to the monitor.

The PC powers up with power going to the fans etc... and the hard drive makes a bit of a noise then it just sits there doing nothing with no display output.

I tried removing various components (graphics card, RAM, ...) to see if that`d help but it made no difference. I thought the motherboard would beep especially when removing the RAM but it made no noise!

I am now running out of ideas of what it could be. One thought was the battery - do these symptons sound like this?

Any suggestions would be greatly appreciated.

Cheers

Paul
 
Loose connection of some sort would be the usual problem after a move, perhaps something halfway connected. Try reseating and reconnecting everything, as you did with the RAM and vid card.

After that I would try a CMOS reset.

Then try removing everything except power, video card, 1 stick ram, and CPU - see if it boots. If a drive or other peripheral (USB etc) is malfunctioning electrically that might shut the psu down, so just go absolute barebones.

If this fails take out that RAM and try another stick. Then move it to a different slot.

If all this fails then you could possibly have a short somehere in the system, mobo to case floor, loose fan wires, etc. Rebuild it outside case and while you are at it check for any damage to mobo such as a bulging capacitor or a burned spot.

If all this fails you likely have either a bad power supply, outputting insufficient power to get a full boot, or else a bad motherboard. Possible video card. I'd try another if you have one.

Is the motherboard speaker hooked up? And do you usually hear a single beep on a sucessfull POST?
 

Grimmy

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Feb 20, 2006
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I'd say it's possible if the battery died, it could prevent it from booting up if:

you had hardware set manually for OC.
or
set for devices that are onboard, but you don't use them, since another PCI device is used.

It helps to list your PC parts as well to help try to figure out what is going on.

Normally if the battery dies, you PC should still boot, and come up with a chesum error, meaning it lost its settings. Athough I've seen on PC not boot because of a dead battery. (Compaq Dual PIII Workstation)

Best place to start in troubleshooting is usually trying to run the MB out of the PC case.
 

pdrnsf

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Jan 7, 2007
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Thanks for the suggestions.

I`ve put the graphics card in and out a few times now so dont know that thats the problem.

I initially thought it might be the monitor cable but have tried it connected to my laptop and its working fine.

If it were shorting somewhere would it not cut the power completely. Its staying on with the fans still running?
 



dbl post
 



Yep, a short will stop it after a split second, so probably not that, but leave no stone unturned, these things don't always follow protocol.

Maybe try an outlet on a different circuit?

I'd sure try a different PSU and video card. What about error beeps? Is the speaker hooked up, usually get a single beep? If it's not hooked, hook it, it might be trying to tell you something.
 

pdrnsf

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Jan 7, 2007
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Yeah i`m pretty sure the speakers hooked up and usually beeps once. I`m not getting any beeps from it at all. I`ve removed everything exept motherboard and cpu and put back gradually but still no beeps. I`m not really sure what else to do now. Will have to try get hold of some spare parts and try them out.
 

atreyu

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Apr 8, 2005
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I would suggest that you try the following:
1. Remove the Video card and memory chips and blow clean and use a brush to clean the sockets and also clean the connectors on the card. Dust can play havoc with your system and simply reseating the cards dont help.

2. Do you have an onboard graphics options, if so try booting using that.

3. Id the monitor light blinking (indicating that it is not receiving signal from the CPU) or is it stable (if stable then you probably have a problem with the video card).

4. This is something that happens to my PC sometimes. The machine starts up fine but it kind of hangs before it reaches the BIOS screen. without switching off anything I simply press the reset button and that seems to do the trick.
 
G

Guest

Guest
I just moved and my computer also has issues like this, it turns on, and the power light just keeps blinking, and after several blinks, it stays on, but the fans are running really loud, and the monitor says no signal to it. After a good while of fiddling with unplugging and plugging it back in, turning it on and off, i finally manage to get it turned on, like right now, it seems to be working perfectly fine, but i'm sure with no doubt its going to turn off eventually again. And it never did this before, only when i moved, im thinking the power outlets in this place suck balls, try taking the computer to a friends house and plugging it in, and see if it works.
 


This is the first thing I would try, given the fact that re-seating everything doesn't seem to have worked.

If you get a signal from the onboard VGA port, it means your onboard graphics have somehow re-enabled themselves and are overriding the video card. That means your BIOS got reset, which points to a dead battery.

Batteries are supposed to last a long time, but you say you've had this machine more that 3 years, and it's not unheard of for one to die in that time. The fact that this happened right after you unplugged the PC from the wall for a prolonged period of time is another red flag. Some machines will have a dead CMOS battery and be fine as long as they're still plugged in and the power supply is switched to on. Then when you unplug it, or if you have a power outage, suddenly any changes you made to the BIOS are gone. Which means that if you had turned off your onboard graphics in favor of an add-on video card, this happens.