Having a problem with pc... Monitor reads "No Connection"

Hi, I am having some problems with my pc and i was just wandering if anybody from the community could help.

When i switch on my pc, the green power light appears and i can hear the fan spinning, but the computer doesn’t boot up.

When i switch on my monitor, a multi-coloured message box appears on the monitor which reads “No Connection”.

I have absoluetly no idea what the problem appears to be so i would greatly appreciate any suggesstions and feedback.

it could be something wrong with your graphics card, or just loose cables connecting your monitor to your computer. I would do the following, whichever is more convenient to do first; try another cable to connect the monitor to the computer, try the computer on a different monitor, then finally try the monitor on another computer. That way you will soon see what’s at fault. Could you also give some more info? How new is the computer, was it custom built or pre built and then bought at a shop/on line, was it working before, etc etc.

Thanks for your response. The computer was custom built as of 2002 from a small, local computer shop. It’s an AMD Athlon 1800, with i think an nVidia nforce 2 chipset. A 32 MB graphics card is built into the motherboard.

The entire system was working fine till about a couple of weeks ago. Firstly it began to crash a lot and then just reboot randomly on itself. I sent error reports to Microsoft and they responded with “There is a driver conflict between hardware or software devices installed on this computer”. I also got the “blue screen of death”.

And now the computer doesn’t boot up at all and the monitor reports “no connection”.

BTW i am using my brother’s PC to post on these forums.

This is most likely a hardware problem; you will need to do some basic diagnostics.

1 Examine the state of the motherboard carefully. See if any of the electrolytic capacitors have leaked or are swollen if so that is most probably the problem. Is the processor and heat sink clean and free from dust if not clean, does the fan run?

2 Measure the voltages from the PSU and see if they are within tolerance or substitute another power supply to see if the old one is faulty.

3 With computer off remove any pci/expansion cards. Un plug all and any connectors to the motherboard reseating them one by one, also remove and reseat the memory card/s. Switch on! If ok then switch off and replace the cards one by one until the faulty one reveals it’s self.

If the above doesn’t cure the problem then the motherboard is probably faulty and needs replacing.

It sounds like the motherboard went to me. Unfortunatlly the only wat to find out is process of elimination. Do what weedougie sugests. Beyond that about all you can do is is start trouble shooting the motherboard components which would require another similar computer. Try the memory in another computer (if it works run it in the other computer and run memtest86 to make sure). Try the cpu in another computer and if good try with prime 95 or another stress test program running. If all weedougie recomended doesn’t solve it and memory and cpu test ok in another system, the motherboard is dead. It would be possible that just the video had died, and you could try a video card if you have one you can borrow, but considering the crashing, That might not be worth the trouble (or risk to the video card).

I wonder if it was a dogdgy PSU that caused it all in the end?

1.) I tried using a different cable between MY base unit and MY monitor but MY monitor still read “No Connection”

2.) I tried MY base unit on ANOTHER monitor but this still didn’t resolve the issue

3.) I tried MY monitor on ANOTHER base unit and MY monitor worked perfectly with no problems.

So the problem it definately not within the monitor, but the base unit / motherboard itself.

I’ll try what weedougie and ripit suggested next but i’m preoccuppied with some other stuff at the moment, so i’ll probably get around to doing it some time next week.

1.) I have examined the motherboard. The electrolytic capacitors show no signs of leakage or being swollen. The heatsink is fairly clean and fan does run smoothly.

2.) I’m not really sure on exactly how to measure the voltages and i haven’t got a spare PSU to try out.

3.) I tried this but still got the same unsuccessful results.

I cannot try out what ripit suggests because i haven’t got a similar computer on which to try out the motherboard / cpu components. My brother’s system (which i am using right now) is an Intel processor and my broken down system is an AMD, so i dont think the components would be compatible.

Even if they were compatible, i cannot physically get into my brother’s base unit and mess around with the components because the system was provided to us by his school and they have padlocked the base unit to prevent equipment theft.

Can you not borrow your brother’s power supply to replace yours?
If the connector to the motherboard is long enough you may not have to remove it from the case, just plug it in to your motherboard, it doesn’t matter about the drives at this point. If the motherboard responds then it’s the psu if not then it’s your motherboard that requires replacing and perhaps it’s time for an upgrade.

i dunno, if u cud try another graphics card on top of a different psu that cud also help eliminate things that might be the problem.

Do you mean plugging in the power supply cable or something else? :confused:

Also correct me if i’m wrong, but if there was a problem with the PSU, then would be possible for the fan to be spinning and the power light to be on? :confused:

The 12volt line may be ok but the 5volt line may be crap, Thats why I suggested you measure the output voltages or substitute the unit. It is a way of eliminating doubt about a part of the computer.
You know its not the monitor and if you pulled all the expansion cards you can be fairly certain that they are not faulty. You are almost there you only need to go a little further or just buy a new motherboard.

I haven’t got a clue why, but my PC just started working again :slight_smile:

I gave the base unit to a local PC repair shop and after a couple of days of testing, the technican there concluded that the motherboard was dead and needed replacing.

I bought the base unit back home, connected it all up, pushed the power switch and for some mystical reason the pc booted up perfectly.

Since then i have fresh installed a clean copy of Windows XP and so far so good, there haven’t been any “No Connection” messages :smiley:

I have to say a BIG THANK YOU to weedougie, gregtherotterius and ripit for helping me, guiding me and offering suggesstions. Thanks alot guys or gals :clap:

if the fan runs as soon as the pc is turned on, isn"t that a default behavior for a heat assossiated problem ??

no its normal,

as for the issue, sounds like a dodgy connection somewhere, if it does it again strip the system and rebuild it. i recently had a molex adapter go after 2 years and it was causing one of my systems to freeze and reboot, the only reason i noticed is because a lit case fan it was attached to kept going dim then bright.

the reason I said this…I overheated my cpu and the system shut down in a similliar fashion, I would get the same no signal on monitor, and fan would be runing, I upgrade my CPU through powerleap.com and on bootup system bios reported a logged heat eror rport

No. If the CPU fan didn’t come on as soon as the sytem was turned on it would melt in a very short period of time. If you don’t believe me take the CPU fan off and place your thumb or a finger ontop of the CPU chip (what makes contact with the heatsink) and power up the system. I bet you you can’t keep your finger on there for more than 5 seconds. How do i know this you ask. I did it once just to see how hot they get. :rolleyes: :eek:

good idea if you want to cause a fire.

I understand that!!, my fan does not emediatly turn on, though boot takes alot of cpu, it is still delayed befor it turns on, I’m not saying thats the problem, but after the shut down, then my fan would emediatly come on. Dell Demension 2400

Every computer i have built (about 30 of them) when you push the power button on that CPU fan comes on, no delay. It powers up as soon as you power up the system. :iagree: If it does not then you have a problem. :wink: