So for the last few days i've been experience this graphic issue. It comes up in messages. What could the cause be. I took it to apple and they said that it's not the graphics card. They tested the machine and it came back fine. Checked it in for the stress-test and it passed. He said it might be software but i don't by. He said because it's coming up in a screen shot it can't be the graphics cards. I had one of my D700 replaced about 2 years ago. Could the other one be failing. Any ideas?