Gem gl-821s only blinks

http://clashofclans.wikia.com/wiki/Gems
Learn to earn gems from here.

On eBay or Google Product Search or Amazon, search
GEM GL-822 power
or
GEM GL-822 12V 5A
There are a number available there. It is 12V DC, 5A

take your RAM out and put it back carefully

Sounds like your power supply capacitors are causing the power supply to shut down. Or you have a short in the monitor loading the power supply. You should try a different power supply.
Monitor Mike

Probably no reset function but a power supply with some failing electrolytic capacitors which can age even when not in use if they were poorly manufactured.

Your monitor is definetly bad....if its under warra\nty take it back for exchange/repair.
If not, ya need a new one.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/sean_54c3a3dc48a7773c

Just lower the screen resolution

Boot into safe mode first by repeatedly pressing F8 and select safe mode
once booted click on an empty area of the screen and take it from there. 800x600 is a good starting point

Re-boot and adust as needed.

Your monitor was just telling you it was too much for it to handle thats all.

Suspected the main board / invertor.

- lower resolution on computer ti 800 x 600 - look on screen to see faint image, if so, then inverter or backlight is gone.

It sounds like a problem on the video / signal circuit board inside needs to have electronic troubleshooting.