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I was replacing my father's computer this past weekend, and he brought up a problem he'd been having with the "new" monitor my cousin recently gave him. ("New" is a very relative term; this monitor was new to my father, but definitely a couple years old. Unfortunately, I don't remember the manufacturer and model number.)

The symptoms started perhaps 2 weeks ago -- that is, prior to me going out there and replacing the system. (So we can eliminate that change as a possibility here.) When he turns on the computer and the monitor, a massive white spot appears in the upper right corner of the screen, then steadily grows to fill the entire screen. About 2 - 3 minutes later, shutting the monitor off and then turning it back on will bring the screen (mostly) back to normal.

(By "mostly," I mean that it will be usable, but you will see what appear to be horizontal refresh artifacts for another 30 - 40 seconds. After that, it'll be fine until the monitor is turned off again.)

Is this an issue with the backlight starting up? Is the monitor on its last legs? Has anyone encountered anything like this?

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up vote 6 down vote accepted

Dead no, last legs, yes!

It really depends on make/model, but this usually means a problem with the back-light / control circuit.

If it is a "few" years old, it may be worth seeing if the manufacturer has a 3/5 year warranty you can claim on.

I had this on a old Samsung monitor, I used it on a server where I only needed to turn it on once every week or so for 20 minutes, it lasted a further 2 years before it finally died (but this was low usage), if you are using it constantly, it would most likely be quicker so get a standby monitor ready!

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Thanks, I'd suspected as much. I actually have one -- I'm going to give him my spare 19" Acer widescreen next time I see him, which itself is several years old, but still a decent screen for his purposes. (Not as good in color dynamics as his, but it's still alive and kicking.) – John Rudy Aug 25 '09 at 14:30

Inspect the power supply capacitors, and any other capacitors. There is an ongoing problem with poor quality capacitors in all kinds of electronic equipment manufactured between 1996 and 2007.

Alternatively, replace the power supply board entirely.

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Yes, It sounds like the capacitors in the power supply are about to go out. This is a very common problem. We repair monitors all the time with issues like you are having. Here is a link to a web page that shows what to look for on the power supply board and what needs to be changed to repair the board.

If you can solder then you should be able to repair your power supply board yourself. If normally involves replacing from 4-10 blown capacitors and then the unit will be as good as new. It's worth checking it out before you trash the monitor.

You could try looking at CCL-LA

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