Recently I have needed to reseat my RAM every few days to get past black screens. It works, then the problem recurs. I tried cleaning the contacts with alcohol and a microfiber cloth, to no avail. I then ran 4 passes with Memtest, which is the most that I can do with the free version. No errors. I will do another 4 passes, but I know that 8 in a row would be better. Still, I'm inclined to just put the money that I'd spend on the pro version of Memtest toward new RAM; the last time I needed Memtest I was probably running Windows 98. I just wanted to see if there was anything else obvious that I should try first.