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Only "red" color partially broken on LCD Monitor?

I searched around and didn't see a problem like this one described.

The colors on my Norwood 17" LCD monitor started looking strange and when I ran the "Color Gradients" test of the CHECKMON program (which I got at

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it was obvious that there was a problem with just the color RED (and colors made up of combinations with RED). The BLUE and GREEN colors were perfect! It's as if the monitor was having trouble showing more than 8 shades of red correctly when it should handle 256. After the top 3 rows, instead of a smooth, increasingly fine gradient from dark to light, there are just 3 main bands/shades of red color and the boundaries between the bands are "jittery". I tested the monitor on a completely different PC - same result so it's definitely the monitor.

When displaying the desktop or most anything but pictures, the problem is hardly noticeable but most pictures show annoying and strange color splotches. They say the most expensive part of lcd monitors is the glass and the glass seems fine so I'm up for trying a repair, but is it a bad cap? A bad circuit board or IC? Any ideas?

Reply to
Al Fei
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Try the LCD monitor on another PC and/or try another monitor on this PC.

The problem could be in your video card or how its color pallette/lookup tables are set up.

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Reply to
Sam Goldwasser

I've tried both and it's definitely a problem in the monitor.

Reply to
Al Fei

Are you sure what you are seeing as red is actually red? On a totally red display, is there any red at all, or is it black?

With a DVM, verify continuity of pin 1 on the VGA cable, making sure it gets all the way to the LCD controller board.

Reply to
JW

CHECKMON also has a "Solid Colors" test - red is red and black is black. No problems apparent with this test at all.

I used different cables on different PCs with the same result. I suppose there could still be a pin 1 break between the jack on the monitor and the electronics inside the monitor but I think that would show more obvious symptoms, not the ones I've described.

Reply to
Al Fei

It looked pretty grim for a while. The "green" color started to go just like the red, and then pure black screens started having a greenish tinge. I opened up the monitor (it was tricky figuring out how to do that without damaging the case too much) and nothing looked burnt / broken so I ended up buying a new one and using this one with a "spare" pc. Today, it wouldn't even hold the sync for a viewable picture! So what did I have to lose? I opened it up again to do a more complete disassembly and found the wire bundle from the logic board to the glass was connected through a special plug/jack that was held together with 2 dabs of glue. Masking tape was also used to hold/stableize the cable to the back of the glass near the connector. The plug had started to unseat a bit on one side so I re-seated it. That was just part of a more thorough inspection of the cards, caps, etc. so I didn't think much of it. I still couldn't find anything that looked really wrong. But lo, on the first retest EVERTHING WORKED PERFECTLY!

The way the mount>I searched around and didn't see a problem like this one described.

Reply to
Al Fei

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