I ran into the issue tonight. I decided to try DX9 for the gene and that was the only change I did. Went back to DX11 and no issue. Running an AMD card (R9) and have 16GB of DDR4 memory. As others have stated, it could be a memory leak and it's just more noticeable in some rigs than on others.

TL/DR if you're running 9.0c, try DX11 to see if it solves the issue.