Answer to: Will not boot, grey screenI recently found this website and it's full of fantastic info. Just wanted to add my 2 cents as well. As a long-time Apple II and Mac user, I've experienced my share of trouble. Don't just reseat the RAM or video cards. While you have them out, take a pink pearl eraser and clean off the edge connector as well. Just a little bit of corrosion on these connectors is all it takes to make these machines go nuts.