pc display problem

[Project2501]

The motherboard dident come with any monitoring utilities, but ill ckeck Dell's website just in case.

When the screen is black, theres nothing going on with the pc, nothing respond (mouse or keyboard). Its on a router with another pc and when the screen goes black the pc stops responding. The power light is on and the fans spin, and thats it.

On the monitor the power light starts flashing, it does that only when it dosent have a signal (it turns yellow in sleep mode).

Im not overclocking anything.

Whats a dry joint issue?

I already tried running it on a tv, the screen whent black after a few minutes.
Ive also tried removing the video card an only using the built in video adapter, same result.

Im starting to think that maybe i cliped or crushed a wire, , cause the case "folds open". And everything is pretty much a tight fit since its a its a mini-tower.
http://apcdigital.com/catalog/images/gx280MiniTower.jpg
Ill check all the wiring again tonight.

[nihil]

OK a "dry joint" is a soldered connection. Over time they become brittle and crack, particularly if you put any sort of stress on them. This tends to produce intermittent faults due to expansion and contraction with temperature fluctuations.

I notice that the tower has some sort of CD/DVD drive on it. When it "goes black" again just try the button and see if the drawer comes out, and will go back, and the little light flickers.

I am curious to see what is still getting power.............as those drives have a direct supply from the PSU via a Molex connector, it might indicate if it is a PSU problem.

Otherwise I wonder if there isn't some sort of chip on the MoBo that handles the communication between the CPU and the video output? It may be having difficulties?

If you set Capslock and Numlock on, do the lights on the keyboard go out when you get the black screen? The keyboard gets its power via the MoBo.

[fourdc]

Dry joint... I'm going to have to remember that one. Thus side of the pond they are referred to as a cold joint. The same thing different name. Usually happen during the manufacturing process, something shakes or moves before the joint has totally solidified. They can be a real b**ch to troubleshoot. Sometimes you can use a can of "freeze"

[Project2501]

Yep the dvd drive works great, opens and closes and the the light flickers too.

I turned on caps an num lock, then at the windows loading screen the monitor flashed and both lights whent off, num lock came back on after a few seconds. So i turned caps back on. When the monitor blacked out for good, both lights stayed ON.

Small orange light in the middle of the MoBo is still on, and network card light is still on. Harddrive light is off ( but its not spining)

[Project2501]

Usb ports still have power, but no connection can be made with peripherals.

[fourdc]

So it sounds like the power supply is doing it's job, you've got 5 volts as the leds are working, you've got 12 volts - the drive ejects.

At some point in the troubleshooting process, we need to start swapping things. Do you have any spare (junk) computers to borrow parts from? If you could swap the video board that would be the easiest to try first.

I'm not saying you should buy a new video board yet, the original may still be good.

If it was a heat problem, you could try a product that's available at most electronic stores. It's a liquid nitrogen spray that cools components. You have to be careful because going from 200 degrees F to -200 can destroy a component as well. You could gently spray into the fans input on the processor or into the video board. One approach would be to choose a component and only apply to that component prior to shutdown and see if you can keep it alive. Another approach would be to cool a component once you've suffered the shutdown.

[nihil]

Hi ddddc, and a happy Easter to you and yours

I think that we can rule out the video card here as it works on another machine. Also he took the video card out and used the onboard video chipset and got the same problem.

I wondered about the connection, but we get the same problem with video card, onboard video and TV out..............so it can't be that.

The power supply seems OK from what we have tested, but I don't know about the 12v supply to the MoBo as it is on a different rail AFAIK. If I had the box on my bench, I would disconnect the power from the MoBo, fire up the PSU for about 10 minutes then meter the outputs.............actually I don't normally even bother with that, I just connect a known working PSU as I have several to hand I would get the PSU tested just to be sure that it is working properly.

I guess that then leaves us with the MoBo and the processor?

My first move would be to remove the heatsink and fan and clean them thoroughly. Then clean off the old thermal paste and replace it with a silver based one. [Follow the instructions carefully: you can have too much as well as too little] When replacing the heatsink and fan assembly, make sure that it is properly aligned and firmly seated.

At this point you need to think about the economics. If the above doesn't work then take the processor assembly to a repair shop and ask them to test it?................ if it is OK, then just replace the MoBo.............it is not economical to get them repaired unless it is something obvious like a damaged connection loose wire or whatever.

[Project2501]

Ill try changing the psu with my other pc to test it when i get a chance .
Ill keep you posted.
Thanks again

[chaosclown]

i have had problems with my network card. it kinda did the same thing. except the screen didn't go black. when i enable it and try to do something else the whole computer locks. the drives worked but the keyboard lights stayed on. even the lights to card worked. i downloaded an updated driver for and the problem ceased. the problem was that there were some conflicts with the mother board. minor fix. yeah right. u recently installed some ram there could be conflicts with the mother board. im not an expert. just an experienced beginner. but it seems that somethings conflicting and its involving the monitor.

[nihil]

Well, the answer to that is simple. Just physically remove the network card if you can. If it is onboard then disable it using system manager (save a hardware profile first)

Might as well unplug the DVD as well (just the Molex) so it isn't drawing power. I don't really think that it will do much, but it would only take a few minutes to try?