[SOLVED] What's up with this ancient monitor?

[kook]

So I have this old CRT color monitor from like 1990 and today I tried powering it on, as well as the computer. So first thing I did is power on the computer and then I plugged in the monitor and pressed its button on the front. Nothing happened. Then I pressed it a little longer and a yellow light pops up and stays on. I can't see anything on the display. Then I press it again and the light turns green and then the green light slowly fades away until there's no light. Still nothing can be seen on the display. Is the fading away a sign that it's broken? Am I doing something wrong? I tried it multiple times. It always fades away.
And yes, I did connect it to the computer.
Here you can see where the LED is on the bottom right:

Also see my previous post for more information on the whole setup: https://forums.tomshardware.com/threads/what-cables-do-i-need-for-this-ancient-computer.3692448/

 

[TerryLaze]

What is the PC doing all that time do the fans spin up? Do you hear hard drive noises? Do you have speakers connected to hear if the windows jingle plays?

It might be a long shot but since the PC has a female plug the monitor might need the signal from the PCs power supply to notice that it should start working.

 

[kook]

What is the PC doing all that time do the fans spin up? Do you hear hard drive noises? Do you have speakers connected to hear if the windows jingle plays?

It might be a long shot but since the PC has a female plug the monitor might need the signal from the PCs power supply to notice that it should start working.

Yes, I heard hard drive noises and fan spinning noises and stuff like that. I've let it run for a while when I tried to get the monitor to work so I expect that the computer was already at some kind of login screen but nothing showed up.
Unfortunately I don't have such cable and I've been told it's optional.

 

[Karadjgne]

Cathode Ray Tube monitors basically use a negatively charged heatlamp to produce a stream of electrons that make the phosphate coating on the rear of the screen glow. This is why screen savers were invented, to stop a CRT from burning the phosphate coating with a single color.

Light bulbs don't last forever. Good chance that electron gun is all used up. Only way to check that is by hooking the pc upto a TV and seeing if you actually do have a signal from the pc or not.

 

[TerryLaze]

Only way to check that is by hooking the pc upto a TV and seeing if you actually do have a signal from the pc or not.

Yeah because hdmi was a thing that existed back in 1990.
He would have to find a second VGA monitor (or TV with VGA input) if the monitor even is VGA and not even older.

Also the power led turning on and fading off would indicate that it doesn't even get to the stage of the screen being the issue and fails before reaching that, so either it needs the system to tell it to start up or it just can't start up period.

 

[Karadjgne]

Yeah because hdmi was a thing that existed back in 1990.

Don't get snippy,

He would have to find a second VGA monitor (or TV with VGA input) if the monitor even is VGA and not even older.

Plenty of Tv's, especially older ones, use D-Sub connectors as a pc input, as do many cable boxes, vcr's, DVD players etc. It's much more likely Op has access to one of those for testing the pc output than another vga enabled monitor. Most likely uses a DE-15 and not the older DE-9 D-Sub as that monitor is most likely SXGA.

While vga doesn't require a handshake the way hdmi or DisplayPort does, the power on signal has 3 points of possible failure. The gpu output, the cable or the monitor input. Power signal comes in, crosses a relay, trips the monitor on. That relay is the first thing inline. If it's toast, you get exactly what Op describes as happening. Same for shutdown, same relay. With no power signal the relay opens and green light goes off. But that could be due to any of the 3 points. Cables do break eventually, especially ones subjected to kinks or hard bends at the connector, monitors fail, gpu outputs fail.

Test what's easy first, eliminate it as a suspect, then tear into the more difficult stuff. Crts don't last forever, same as the guns on the old projection screen Tv's, they do fail after years of use and that monitor is somewhere around 20years old and could have suffered untold abuse, we don't know it's history over those years.

 

[kook]

Most likely uses a DE-15 and not the older DE-9 D-Sub as that monitor is most likely SXGA.

It's actually a rare 14-pin VGA port and I can't find any adapter for it at all.

 

[Karadjgne]

Ohh. Not really.
Ok, it's a 15pin. Sort of. They both work the same. However, that missing pin in the middle row is a 5v DDC used by flat-screen (plasma/LCD) Tv's to send data to the gpu about the native resolution. The rest of the pins are the same. All those old crts used the same 14pin setup, it was only changed to 15pin to accommodate those flat-screen Tv's.

For your use, on a CRT, you'd need a 14pin, which was common for VGA. You do not want a full 15pin connection, your gpu will have all 15 pins to accommodate using a TV. As long as the monitor or the cable has pin #9 missing you are good.

Push comes to shove and you cannot find a 14 pin, only a 15 pin cable, just take some needle nose pliers and snap that extra pin off or your gpu will think the CRT is a plasma TV.

 

[kook]

Ohh. Not really.
Ok, it's a 15pin. Sort of. They both work the same. However, that missing pin in the middle row is a 5v DDC used by flat-screen (plasma/LCD) Tv's to send data to the gpu about the native resolution. The rest of the pins are the same. All those old crts used the same 14pin setup, it was only changed to 15pin to accommodate those flat-screen Tv's.

For your use, on a CRT, you'd need a 14pin, which was common for VGA. You do not want a full 15pin connection, your gpu will have all 15 pins to accommodate using a TV. As long as the monitor or the cable has pin #9 missing you are good.

Push comes to shove and you cannot find a 14 pin, only a 15 pin cable, just take some needle nose pliers and snap that extra pin off or your gpu will think the CRT is a plasma TV.

Oh, that actually sounds like a good idea. Are you sure it will work and it won't be broken?

 

[Karadjgne]

As long as you get the right pin. Found this, pretty much what I said, but explains it better. With pics.

14 Pin & 15 Pin D Connectors on VGA Cables

Introduction I wanted to know what the difference is between VGA cables with 14 pin and 15 "D" connectors. I found the answer on the Instructables site/forum

helpfulcolin.com