Computer Screen Goes Blank

Humble Ess,

Does your PC have a "component" video card, or is the video circuitry included on the motherboard?

It sounds like the problem is that some component is overheating - very likely the video processer chip.

Have you checked that all of the cooling fans are functioning properly, and there is no build-up of dust on any ventilation grilles or interior components?

Did the PC's motherboard come with diagnostic software?

(If not, you may be able to download one from the manufacturer's web site)

Many such diagnostic programs will actually report the temperature of key components, as well as the actual rpm of the system's cooling fans.

If the problem is a moving target (hard disk 2 weeks ago, then video,...), then look for the common link. Check your power supply.

Another thing to look at besides the power supply is the capacitors on the motherboard and the video card. Look to see if they have domed tops or are leaking some brownish liquid. Not to long ago these were the source of many problems such as you describe.

Just as an aside, these problems were addressed by major board manufacturers after a couple of the big ones were sued. Of course, they bought their caps from the cap manufacturers.

If that computer is out of warranty...buy a new one.

The headaches don't justify the troubleshooting. It is not cost effective.

We call it as soft trouble, not easy to solute sometimes

If the crt blank after work a few hours, you can check either display card or monitor itself. mostly because caused by some parts aging. sometimes capacitor leak very much.

the best bet is when it took place, lind the crt to oher computer, if it display normal, the problem is on mainboard, either card or cpu itself.

open your framebox, check cpu fan is right running, if not, change one .

check your card fan to see if it run normal and test temperature of chip by hand back

chang fan or oil its bear. to keep it run well.

If its problem is crt, I suggest you buy one new lcd display instead of your old crt.

I dont suggest you repair it. becasue there are very higher voltage in it. if yhou dont familiar with ciucuit, it dangerous.

mostly the problem is at hv generator especially second hv part, this part insulator fail. the screen will fate out gradually. change one. alhough its cheaper verymuch. but you would let electric worker help you .

Please check your display settings properly .also check RAM ,this was common with older PIII /PII , when RAM contacts caused problem along there slots , please check this also , also heating of perticular component cannot be rectified by applying heat sink jelly alone , issue proper ventilations

If you meant to say that your PC switches off immediately the first time when cold, and the CPU is correctly cooled (its practically the only bit that can heat up quickly enough to do thsi), then it is not a heat problem. Especially if after switching on again it works for some hours....

I would suggest a bad power supply, or maybe the load is getting too large, on the edge so to say.....

Start fault finding, remove all cards except one memory board and the video card, if it stays on, then you have removed the problem bit OR it is the power supply and the reduced load has helped.

Place each memory card, one at a time back (on its own in the PC) test with a good free memory test....

Replace each card in tun and power on. If you cannot identify anything further, replace the power supply with something much heavier.....

Thanks & regards for your remarks & additional info on the subject.

Title "Monitor Screen Goes Blank" is the proper Title for the Question, I think.

To start with:

It is surely not RAM @ fault because PC does not boot if RAM is at fault
& a double-beep is for Memory problem.

Try to distinguish between Power LED & HDD "Active-LED".
Power-LED lights continuously while HDD-Active LED flashes [at irregular timing].

During Boot-up CD & Floppy or Remove-able drives lights blink one after the other.

1. Remove all the "Cards" except "VGA" if not built-in Mother Bd.
If it is Integrated in MB try an External VGA Card.
Note: You may need to modify BIOS to look it 1st.

2. If problem persists then nothing is with any Card or built-in VGA [if it is]

3. If problem is solved then try 1 by one inserting cards.

4. Do not remove the inserted card if the system remains OK & try the next.

5. Normally PSU failures may cause such problem of "Intermittent" problems, especially aged one.

6. To check PSU Voltages, System temperatures, excessive noise in PSU's output etc there is a
Free SW named "SpeedFan" @ <http://www.almico.com/speedfan.php>
or direct download: <http://www.almico.com/speedfan432.exe> if Ver 4.32 is still the latest Ver.

7. Monitor may be the culprit but the least. However clean it with a blower if you some hand on it. Try to check with another one to make sure it is OK or other-wise.

I know that you only wanted to help, but you made some serious errors when you said:-

It is surely not RAM @ fault because PC does not boot if RAM is at fault & a double-beep is for Memory problem.

If that part of memory is not used during boot up, or it is only sensitive to a certain pattern of data or even voltage, you will not always get beeping at boot time.... Obviously your experiences are limited in this area to go or no go memory, mine are not!!

Here is another area of "lack of experience" shown with the next statement:-

5. Normally PSU failures may cause such problem of "Intermittent" problems, especially aged one.

It is possible for it to go intermittent, but that is usually relatively easy to spot, but if the PSU is faulty in another way and simply cannot supply the full amount of current required, or is simply not big enough for the job as extra cards have been added since new, or the fan is full of dirt and so is the main heat sink, which means that the PSU is overheating slightly, then you will not have the problem again probably till all the cards are in TOGETHER and it has heated up fully.

So in practice it is best to test each card (other than the VGA card once it has been proved OK) one after the other to see if they are working when NOT with the other cards....so take each "good" card out before testing the next one, or you will replace the last card as it seemingly "caused the problem", but in reality, it is not the problem at all.....any card as the last card may cause the problem!

This is a difficult one for amateurs I know....both to understand and fix.

The next failure is really dangerous:-

7. Monitor may be the culprit but the least. However clean it with a blower if you some hand on it. Try to check with another one to make sure it is OK or other-wise.

If it is an LCD monitor, it is best not to open it up as it is easy to do more bad than good, try a different monitor and see if the problem is fixed. Only let a professional open it up for fixing..

If it is a CRT monitor, opening it up could be life threatening, especially if you have heart problems as even switched off, for many months even, a very high voltage can be retained on the screen itself and touching the wrong wire can at best be very, very painful. Borrow another monitor for testing again! Only let a professional open it up for fixing..

May I also add that opening up a PSU to clean it out or replace a defective fan is NOT FOR AMATEURS either.......there is usually a sticker saying just that, take heed of the sticker.

Also, even for the simple, low voltage stuff as you do not know what has gone wrong, you should always tell amateurs to remove the power connector before working in the PC and to use a proper, resistive antistatic wrist strap, attached to the computer metal frame of case when handling parts as they can be damaged when a hand with 1000volts charge goes NEAR to them. Always lay the parts on conductive foam or aluminium sheet or a metal table when not in the PC.

You need about 6000volts static charge to even feel it or see it as a small spark!!!

Some CMOS Chips cannot handle even 50 volts on a pin!!!

Having 60,000 volts charge (or more) on your body, in a European winter is not unusual....man made fibers in your clothes or in the floor covering and rubber soled shoes are a bad configuration (or good depending upon your standpoint!) for producing high static charges....

Remember, it is what you don't know that usually kills you!!!!

The rest of what you said was reasonable I feel, or not so badly wrong to worry about!!!

But if you yourself work in this untidy and unsafe manner (I did not mention all the other possible dangerous things that can happen to your PC or yourself), you will eventually do something really dangerous and kill yourself.

Please look at the following website for further infos in this matter:-

http://darwinawards.com/