LCD screen keeps going black, backlight issue?

[djm232]

Today, while I was doing some gaming, my Samsung SyncMaster 931bf {link to random review of monitor) screen suddenly went black, but I could still hear audio. The power LED was still on, so it didn't actually shut off. First, I thought the game had just bugged out, so I tried alt tabbing in and out to no avail. I can't recall if it came back on by itself or if I toggled the power button, but it started working again so I went back to playing my game.

About 2 hours later, it did the same thing. Toggling the power like before will get it to come on for about 2 seconds, then it goes back to blank. It also makes a faint "squealing" noise while the screen is on, like the one cheaper power supplies make.

I bought this monitor new in a store about 2 years ago now. I've taken great care of it, and it's never fallen off my desk or anything. About how diffucult would it be to replace something like a backlight by myself, if that is the cause of this? If anything, this gives me a good excuse to finally upgrade to a widescreen.

I'm on my old CRT for now. I'm going to hook the LCD back up and see what happens.

Thanks for looking.

edit: Did some more tinkering, I can reliably get it to turn on for about 1 second each time I toggle the power button, so the backlight can't be totally burned out. It makes a decently loud "fizzling" noise and flickers a bit when it's on for that one second.

edit 2: Did some googling, and it sounds like the inverter is going bad. Anyone have any experience with these, or has replaced one on their own before?

 

[Whoisthisreally]

I am reminded of the behaviour of my five year-old BenQ FP71E. It too has backlight issues such as a blank screen whilst the power LED is active.

Unlike your problem, my screen tends to only present the problem when freshly turned on at the start of the day, usually fixing itself with 15 minutes or so. At some point it proceeds from a blank screen with the backlight turned off, to repeated restarts of about three quarters of a second in duration.

Eventually it gathers its senses, stops restarting and starts functioning normally, albeit with a harsh flicker for a few moments. Funnily enough, a precisely imparted tap or blow can make the monitor perform normally for upwards of a minute before resuming a blank or restarting screen. Usually this prolongs the problem, so I tend to turn my machine on and leave it to make a cup of tea. For a fairly old monitor, I am pretty happy to accommodate the fault while I wait for the new LG IPS models coming in June/July.

 

[Elledan]

CCFL backlights are hard and expensive to repair, if at all. When one dies it's generally cheaper to just buy a new monitor. If you're really handy with electronics and the part(s) to replace aren't too expensive you could perhaps fix the inverter, but it is part of the monitor's other PCBs and thus you risk damaging it even more.

Whoisthisreally's monitor seems to suffer from bad solder joints.