Engadget reports a number of users of Apple's new 17" unibody MacBook Pro are experiencing graphical glitches. At first, people pointed to the NVIDIA GeForce 9600M GPU but it seems the problem may be caused by a faulty fan controller:
While we first assumed that it was NVIDIA's GeForce 9600M causing all the mayhem, further investigation has led us to believe that faulty fan controls could be the culprit. Granted, all of this is just speculatory at the moment, but it seems that some users have noticed that their fans aren't kicking into high gear when they should. 'Course, some folks have seen those RPMs spin up while the funky lines and psychedelic colors remain, so it's still hard to pinpoint a definite root cause.