:confusedProblem started when Mbp froze during music play in iTunes. No mouse or keyboard function so I did a hard reboot. Came back up ok but then screen went to horizontal multi-colored lines. Re-loaded OS-X Lion. screen was fine during the entire process. re-boot was initiated from recovery partition. Screen was ok for a few and then lines again. Re-boots great in safe boot mode with no screen freeze,etc. recently upgraded from 120 GB HD to 500 GB and bumped RAMM from 2G to 3G. Pulled the new 2G stick and put the 1G back but no change. Not sure what to do next. Any input would be greatly appreciated.