I've used an LG IPS234V LCD monitor since 6/2013. A few weeks ago, I started using it at 100% brightness, which I should have done a long time ago.
About a week after that, the monitor would fail to turn on and stay on. I would turn on my PC and monitor. The monitor would turn on for a second, then turn off, then back on. Flickering on and off every second. Eventually it would stay on.
I found that if I set the brightness back down before shutting everything down, the monitor would be able to turn on the next day.
Sometimes, I would forget and would have spend time to get the monitor to stay on.
I opened the back of the monitor in search of bulging capacitors or burned components. I didn't find any.
I searched online and others had the same blinking on/off, but didn't have a solution. One had fixed theirs by replacing a capacitor and voltage regular in the back of the monitor. One or two others had hissing noises, fixed by replacing the power adapter.
The power adapter for this monitor is an external AC-DC adapter and connects to a DC jack on the back of the monitor.
The monitor's back label specifies 19V 1.3A, but it comes with a 19V 1.1-1.2A (I don't remember how much exactly) power adapter.
Maybe the increased brightness and age caused the power adapter to fail.
Opening the power adapter, I found a capacitor that was bulging. The capacitor was one made by Su'scon, with markings SG 105 degree 1305(M), which is a 680 uF 25V capacitor. I was going to replace it, but found that it's a low impedance or low ESR capacitor. I didn't have any and didn't want to replace it with a normal capacitor, so I decided to cut off the power plug and put on another adapter.
I found a 19V 2A laptop power adapter, cut and spliced the old plug onto it. The new power adapter worked. I have been able to keep the monitor at 100% brightness, and it turns on without issue. This has been working for about a week and half, so I'm confident it's fixed.
Now, I can keep using and don't need need to rush to buy a new monitor.