I changed a computer processor from amd r5 3600 to amd r5 5600G. I updated the BIOS to F13 before changing the processor and the computer started and when I wanted to play some games I found vram 512m. So I decided to change it from BIOS (I have 8GB Ram) so I made it 1gb but when I saved it .it came back to the BIOS menu So I put it back as It was 512 and I saved. But when I restart the black screen appears. What is the problem, knowing that when I restore the old processor, the computer booted without a problem?