I relate a failure I had that may prove useful for other MBP users who have similar symptoms. I had a failure of my MacBook Pros GPU. I just got it back after Apple fix. What I noticed in the months leading up to the event was the fans running and the machine getting HOT even when little was happening I had iStats up, with temp and fan RPM. I am trying to recall the symptoms form memory here. Before: The fans went up to clearly audible level at about 127* F, and it went up to a high RPM (about 4000 RPM). After repair: Under high load temp went up to 160* F, fans at 2000 RPM. It slowly (over 2-4 minuets) when up to 4000 RPM. Even then runs noticeably quieter then before. FAILURE details and strangeness after of old board: I was watching a YouTube video when it suddenly stopped and some parts of screen showed corruption, especially around the mouse. The MBP froze hard, would not respond to anything except a hard shutdown. When I rebooted the screen showed the logo and twirl, but stopped at a light blue screen just before the log in window. I restarted and with Option key could see my selection of drives, and chose my Windows partition, but that too would not go into GUI. When I tried a system DVD, it too went to light blue screen. I tried Pram reset, except for brighter screen, nothing. I WAS able to get into Target Disk Mode, with the famous yellow Y bouncing around (and that allowed me to make a final backup of the drive). A friend of mine also had his video fail (this time no video at all), but his TDM worked perfect, so he did same. He did not have any backup) At the Apple store their diagnostic software displayed completely, showed status on all components. Did indicate a logic board flaw. Other software they tried to boot into failed (again, full selection of devices showed. It was seeing the screen display low end system items makes me believe the Mac ROM has basic video functions that is passed to GPU when system loads.