Green flickering in games

[castehard]

I bought a used monitor. So as in title when my gpu gets hot I got green flickering dots(?). Monitor is 23inch (2048x1152) - only vga output. I connected to my gpu via VGA cable and HDMI connector to gpu (when DVI connector the screen is flashing on and off).

 

What is the cause of the dots? I think it isn't monitor fault bc it was working fine before.

 

Can someone help me?

 

Should I change the cable or something?

[Abdullah Bhutta]

11 minutes ago, castehard said:

Should I change the cable or something?

You should at least try to change the cable.

Is your GPU new and under warranty?

[castehard]

21 minutes ago, Abdullah Bhutta said:

You should at least try to change the cable.

Is your GPU new and under warranty?

I will try another. No it's old r9 280x but on my previous monitor(vga cable and dvi connector) it was working fine

[Abdullah Bhutta]

25 minutes ago, castehard said:

I will try another. No it's old r9 280x but on my previous monitor(vga cable and dvi connector) it was working fine

then its your Monitors fault

you should have bought new instead you are left with big problems now