Monitor goes off after an electric buzz

我的问题

I have this old monitor for an year now on my desk, and 2 weeks ago I tried to plug it in on my pc to the motherboard due to my graphics card being an old model I used the VGA port from the monitor plunging it to the motherboard cause the graphics card port has DVI and uses an adapter for HDMI to use my graphics tablet

The motherboard is an :Gigabyte H81M-S2H

The graphics card: Radeon RX 470 Mining edition with a DVI port (only port)

The processor: Intel I7 4 Gen

The PSU: i am not sure cause I bought the whole pc second hand.

The issue is all of a sudden while drawing and listening to music I heard an electric like buzz and both my monitor and the graphics tablet turned off but the tablet remained on while the monitor not. And since I live in a old house with old electric cables, in an country side an small village i thought it was an electric condense. Or something cause it happened all of a sudden.

What should I do i am worried cause the monitor that is showing in the picture was taken home from the streets in Germany since there's always goods that are thrown out and being taken by others.

我的修理方法

What should I do and how to repair this issue. Also I am an broke person.

我的建议

Any advice about this Cause I am broke and can't afford to buy a new one cause of living in an poor eastern country.