Need some computer help... Monitor shuts off for no reason.

[enhancedstudios]

OK... I built a computer for someone a month ago, and it was working fine (except for I can't get the sound to work for some unknown reason...) but anyhow, everything else was working fine... and then the other day she says it just started shutting off... so she brought it over today... and I turned it on, left it on for about 30 minutes, and sure enough... the monitor just turns off. The computer still keeps running, nothing else changes... Just the monitor light turns from green to orange, it goes black... and then the only way to get it to come back on is to restart. It's happened with two separate monitors, so it isn't a connection problem... turning the monitor on and off does nothing.

What could this possibly be?

[tacos4me]

Do you have it on hibernate mode? I had an old machine that turned the monitor off after awhile and wouldnt come back on if i moved mouse...turned off hibernate and worked fine. Go into screen savers then "Power" and make shure all boxs are set to "Never".

[enhancedstudios]

Well, actually I tried that... and it hasn't done it since then... so it appears as though that fixed it. However, I don't quite understand why it would have been a problem to begin with though... because she said that sometimes it shut off on her right in the middle of doing something... and there is no hibernate button, and it obviously wouldn't have done it if she was actively using the computer. It was set to 10 or 20 minutes I think.

Confusing.

[Soyoman]

Would this be a Compaq monitor per-chance?

[enhancedstudios]

possibly, I'll have to check. I think it's an HP though. It used to have monitor mounted speakers. It's fairly old. Maybe 4 or 5 years now. Why?

[enhancedstudios]

Well, looks like the monitor is fine... but...

It ran for about 8 hours fine with no problems whatsoever at my house... I gave it back to her... and she called me about an hour later and said that the whole computer had shut off and wouldn't come back on. So she brings it back over here today... and I plug it in... nothing happens. Won't turn on... so I mess around with the insides a bit... I discover that when I move the cmos jumper from 1-2 to 2-3 and back, then when I hit the power button, the light in front flickers, but nothing happens... so, building on this, i mess around some more... nothing happens no matter what unless I switch that jumper... and then it still only flickers...

Then, I decided to try something with the power supply. Currently it's got the main ATX cable plugged into the board... and it's also got the smaller 4 pin square plug plugged into the board as well... i try turning it on without the main cable.. nothing... i try turning it on without the small 4 pin cable... nothing... but then i decided to plug in just the big main cable... and not the small 4 pin cable... move the jumper to 2-3 and back... BAM. It comes on again. Only, the monitor won't come on..... the computer doesn't beep or anything. Powers on just fine, but absolutely nothing happens.

So...

What the!??

[tacos4me]

Have you tried a different PSU?

[enhancedstudios]

I'll have to take the PSU out of my computer to test it. None of the rest that I have are powerful enough.

What is the smaller 4-pin connector for, exactly? Does it power something that would be required for the monitor to come on (it does have onboard video and sound)... or does it power something that needs to kick in for it to boot up?

[Soyoman]

The reason I asked what type of monitor is because if it's a Compaq P75 then it's the monitors onboard computer. It's really picky with some graphics cards. The one I have doesn't like my GeForce4 MX440SE, I switched to a Gateway EV700 and now it works fine.

Anyway, it's probly not the problem. What Wattage is the current PSU? And what are the full specs. of the machine?(ie, # of drives, ram, etc.)