Someone trashed a monitor. I took it home. It is a discontinued Insignia 24” LED 1920x1080 monitor from 2013. Model name is NS-24EM51A14.
Plugging it showed no signs of life. I disassembled it. Thankfully it was very easy. It uses snap-in bezel and some duct tape to keep stuff together inside.
As I was disassembling it, I noticed a loose flat ribbon cable, but thought it’s just something for diagnostics. I removed the metal shield box, and in it was power supply and main boards. I checked power supply for blown fuse or leaking electrolytes, but didn’t find any issues. Then it dawned on me, I checked the bezel and found it had a control PCB in it with a connector for small flat ribbon cable! I reapplied sticky metal and duct tape as it was before, reconnected the cable to the bezel, and snapped bezel back. Tested the monitor and it works!
Sadly it’s not a great monitor. Poorly built, with horrible stand, as expected from Bestbuy’s store brand stuff. In it’s hey days it sold for 120$ and was 80$ on sale. I’ll be lucky to get 20$ for it. But since my awesome Dell UltraSharp 2405FPW is loosing brightness fast, I may even end up using it.