I've got an early 2011 15' MBP (2GHz i7) running snow leopard. I was getting kernal panics and other scrambled looking screens. I take it in to Apple only to find out that this is a known problem. So they replaced my logic board for free. However, I got my computer back yesterday and it's still got some artifacting, or scrammbled screen going on. ANYTHING else this could possibly be? I've tried a new HD and swapped out the RAM Thoughts?