Sorry been away this weekend, Those artifacts can be caused by poor drivers, overheating and overclocking, try updating the drivers to the latest version. You're not overclocking so that's not the cause. I would say it's drivers or overheating. But you''ll be using the 7770 in a while so no need to worry about the on board GPU anymore. As for the REV 2.0 issue thing, nothing to worry about, it will still work regardless of having win 7 or win 8 installed, I think you are referring to the card having a UEFI bios, meaning it will boot faster with windows 8 installed, but will work without issues. My 7870 myst edition worked flawlessly on my old motherboard bios that was dated 2010, and it's been said your motherboard must have a bios release after Oct. 2012, It's a windows 8 compatibility issue, don't update your bios now.