Nec flat screen goes blank after 20 seconds

Most likely the power supply. Bad capacitors, if you think you can solder in new ones, good. If not; buy a new monitor

This is happen due to power problem please check your power connection due to power fluctuation its happen.

Does the power light stay on? If so, you have an inverter problem. If the power light goes off, you have a power supply problem.

Bad capcitor in the psu would cause this to squel and even pop so have it looked at you be glad you did.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/edwy_1a56970cf1ea4620

Hi ,
The monitor flicker problem. The monitor when turn on will display image for couple of second then turn black. The monitor status led is still green. This will happen each time it is turn on. The symptom at appear to come from the inverter board.

I returned the monitor for a full refund. I'll keep shoping. Thank you for your responce and drop me a line from time to time. dipper19

Beautiful screen, lasts about for a few minutes, goes black. Power button still green. If I turn it off, and then back on, it works again for a while. Any ideas?

F1 = Fuse 1
You should be able to locate a surface mount fuse at your local electronics store.

I start my computer and turn it on, and everything looks fine for about 1/4 of a second and then it goes black while leaving the power light green. I can only see the screen again after turning it off and on, but that's only for another 1/4 second. What's up?
I got my rosewill flatscreen as a hand me down from my father. I've had it for several years now. Was working fine until a month ago. When I turn the computer on the screen goes black after 1/4 of a saecond. I have to turn it off and on anywhere from 10 to 20 times before it stays on. I have checked all plugs to the computer and outlets. I have absolutely no idea whats causing this.

The LCD screen may be burned out. There's whats called an invertor board and there is an electronic ribbon strip on the LCD itself. If you look very carefully you can probably see a faint image on the screen. The LCD screen will need replacing. Before doing anything with this monitor, try it on another computer first and if you can try another monitor on your computer. Other than that, there really is nothing you can do but replace the monitor.