I have a NEC LCD1912 that is trying my nerves. Somebody gave me this thing because it would not power on at all. Please keep in mind that I'm not very experienced or knowledgable about fixing these things; it's sort of a hobby / learning experience for me and so far I've only managed to muddle my way through about a dozen or so LCD monitor repairs. Ok, back to the problem. I opened it up to give it a quick look over and notice that one of the caps on the video board was only attached by one lead (I think it was a 16v 10uF). Now being that I'm not a pro, I don't have a lot of spare parts laying around, but I just happened to have a few of these. So in the interest of my personal entertainment I went ahead and replace all of the 16v 10uF caps and also a couple of the 16v 22uF one, just because I had them and I figured it couldn't hurt. So I put everything back together and the monitor powered on, yay! All the buttons worked and everything was happy. Then after about 10 minutes the video went out, not the backlight, just the video. (By the way it has 4 backlights and I also built a little rig to test out the lamps, and as far as I can tell they all work fine.) Ok, so now the backlights are lit, and so is the green power led, but no video. Also, if I push the power button, or any button, nothing happens. I have to unplug it to power it off. If I plug it back in and try to turn it on, nothing happens. I tried all sorts of different things to try to get back on, and here's the weird part. In order to turn it on, I have to disconnect the VGA cable, then plug the power cord in, then turn the monitor on (if it doesn't come on by itself), and then plug the VGA cable back in, and it works fine, until it cuts off again, which could be anywhere from 2 minutes to several hours. But it will come back on 100% of the time if I follow this procedure. It seems as if the VGA cable is causing the power supply to short or overvoltage preventing it from powering up, but once it is already on, it doesn't affect it until some time later, which is where my ignorance comes in to play, because that just doesn't make any sense to me. So if anyone has any ideas, I would really appreciate some help. If this helps, the power supply and inverter are on the same board and there are still some slightly larger caps on the video board that I didn't change out, simply because I don't have any around here at the moment.
Oh also, on a similar note, I have a HP F1503 that works fine, powers up, displays the test image and everything, but as soon as you connect the VGA cable from the computer to the monitor, the whole thing blacks out. I know the problem is in the video board because I switched it out with a good working one, and that fixed it. It would be great if both my problems had a similar fix (if its an easy fix anyway).
Sorry for the long post, I tend to ramble when I'm tired. Any help would be greatly appreciated. I don't have much to offer in return, but I be happy to buy you a beer or two if you can help me out! (New Orleans area only)