HP monitor flickers

[ironwill99]

I had a customer donate a HP m90 19" montor to me but the bad news is that the brightness randomly increases and decreases. The magnitude of the change in brightness is just enough to be annoying so it is not too severe. I was wondering if there was a fix for this. Thanks.

[Outcoded]

Not an easy one, no.

[ironwill99]

Not an easy one, no.

Well then what's the hard one?

[cisco2]

I have had some (limited) success opening up monitors, replacing fuses and repairing failed solder joints. I've never been successful when attempting to replace suspected failed components though.

If you're not familiar with the electrical hazards present inside a computer monitor I wouldn't recommend trying.

If you are, be careful but open it up and have a look see. This sounds like a component is failing (rheostat or varistor or something of that nature). If that's the case you're not likely to be able to do anything to fix it that would be worth your time or money. Sometimes you get dust build up that can cause overheating problems and you can clean that up (be very careful, blowing compressed air over electrical components can cause static charges to build up, some compressed air lines get oil or moisture in them too, blowing water or oil over electrical components = bad). Sometimes you can identify a cold or failed solder joint that can be repaired. Once in a great while I fix them by replacing a blown fuse but that's rare and won't be the case for you this time anyway.

CRTs can hold a substantial charge for a very long time. Effectively they are a large capacitor, that suction cup on top protects the anode. I've never shied away from working on CRTs but many (most?) prudent, safety conscious individuals don't do it. Without proper training and equipment you may not be able to safely avoid the electrical hazards.

If you're not into component level repairs, it's probably not worth it. Even if you are your chances of success are low.

[ironwill99]

Well I gues you are right. I do know that monitors and TV's are dangerous to work on. I was just hoping I could get something good out of this thing. Oh well. Maybe Goodwill will find a nice home for it. (I really don't want to toss it)

[slgrieb]

Been out of Austin for 10 years, so I'm not sure about local repair services, though I know of some in Dallas and San Antonio. I take my marginal monitors and use them on the bench for data recovery and stuff where display quality isn't an issue. I have suppliers in Dallas and Houston that will sell me a Class A 19" refurb for something like $75. That kind of pricing makes any depot service really unattractive, so I don't have any monitors repaired or repair them.

Have you checked out the Dell outlet? I remember 2 page adds with all kinds of refurbs over in the Statesman's Biz and Tech section.

If you just want to look at component-level repairs for monitors, Amazon has a book that discusses common componenet failures on specific models of monitors. Sorry I can't remember the title, but I bought it a couple of years ago, read it and threw it away. Just not cost-effective.

[Goingincirclez]

I had a 19" MAG that only cost $289 new back in 1999. Yeah, you get what you pay for and this thing was a piece o' crap, and about a year later it displayed the random flickering symptoms.

Later on it would just fade out entirely, and then with a good smack it would fade back in.

I was able to rectify this by taking an old case fan and rigging it to a 12V power adapter (if you're really really good you could probably rig it to the monitor's own power supply but I would not recommend trying that!) I mounted this to the top of the montior's plastic casing to help exhaust the hot air out. Believe it or not, that helped and for about a whole year I had no more problems! (The monitor did eventually start exhibiting the symptoms again, and I used it for a bench monitor before giving it to someone needier than I).

I had a friend who inherited a 21" monster with similar problems. He took the plastic casing off entirely and ran it like that. Dangerous to be sure, but it did have an internal metal sheild and he was very mindful of this hazard. He got his fair share of good use from it before eventually chucking it.

I also had an old PB 14" that blanked out... I'm not monitor tech but I found that the CRT would "sag" against some other component and that was making the signal go out... I very carefully wedged some legos (only solid non-conductive thing I had handy at the time!) in there and got 3 more years from it.

Bottom line is how badly do you want to save it, how much are you willing to possibly learn? You don't have anything to lose from trying, BUT as others have said, be very very VERY careful with an exposed CRT.

Hope that helps...

-Tony

I had a customer donate a HP m90 19" montor to me but the bad news is that the brightness randomly increases and decreases. The magnitude of the change in brightness is just enough to be annoying so it is not too severe. I was wondering if there was a fix for this. Thanks.

[ironwill99]

I had a 19" MAG that only cost $289 new back in 1999. Yeah, you get what you pay for and this thing was a piece o' crap, and about a year later it displayed the random flickering symptoms.

Later on it would just fade out entirely, and then with a good smack it would fade back in.

I was able to rectify this by taking an old case fan and rigging it to a 12V power adapter (if you're really really good you could probably rig it to the monitor's own power supply but I would not recommend trying that!) I mounted this to the top of the montior's plastic casing to help exhaust the hot air out. Believe it or not, that helped and for about a whole year I had no more problems! (The monitor did eventually start exhibiting the symptoms again, and I used it for a bench monitor before giving it to someone needier than I).

I had a friend who inherited a 21" monster with similar problems. He took the plastic casing off entirely and ran it like that. Dangerous to be sure, but it did have an internal metal sheild and he was very mindful of this hazard. He got his fair share of good use from it before eventually chucking it.

I also had an old PB 14" that blanked out... I'm not monitor tech but I found that the CRT would "sag" against some other component and that was making the signal go out... I very carefully wedged some legos (only solid non-conductive thing I had handy at the time!) in there and got 3 more years from it.

Bottom line is how badly do you want to save it, how much are you willing to possibly learn? You don't have anything to lose from trying, BUT as others have said, be very very VERY careful with an exposed CRT.

Hope that helps...

-Tony

Thanks! Welcome to Windrivers! I will take a peek inside it and see if there is anything obvious but I am not willing to go further than that, at least for the time being. I am always willing to learn new stuff so maybe I will check it out this weekend.

[delmer_1]

You don't have anything to lose from trying,

except your life.

[ironwill99]

except your life.

That's actually funny since I just got a life insurance policy. I will have to watch my back while I work on this because my wife might try to take me out. I check my break lines every morning now just kidding.

[DocPC]

Check the cable. I have had a lot of HP cables get kinked and had to repair them.

Move it around and see if it changes the colour/brightness. Usually the end closest to the monitor.