After this Mac had a busted power unit which also killed the graphics card. A Nvidia 610 was used as a replacement. I do mostly Photoshop work on this machine and using the latest CC version I've noticed some rendering issues that I think are linked to the card. What would you recommended as a replacement? I'm using 10.10 Yosemite and would prefer not to have to flash a card. Ideally I'd just buy one of the older supported cards 2nd hand.