im sorry i meant the memory of your graphics card.
run memtest on your ram for a few hours and that will tell you if your RAM (the actual sticks in your computer, not the graphics memory) is stable or if it has problems.
Memtest86.com - Memory Diagnostic
oh wait i see in your original post that you ran memtest. did you get no errors with it? or could you just not see it because of the problem you are having?
try re-posting your screenshot so i can see it.
what motherboard do you have?
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