My lovely new 17" penryn standard res (old style, not the new LED) screen has developed a random flicker that makes the light flicker like an old flourescent light about to fail for some 10 to 30 seconds and then stops again. It's subtle but eye watering. It took about a week to show up the first time and is quite intermittent. I can be using SketchUp or reading on the net with Safari. Rang Apple the first time and the guy talked me through a complex process to try and fix it and it was fine for a couple of days but now it's doing it again and this time Apple want me to trail into a Genius bar which doesn't thrill me at all. Anyone else have any ideas? For the sake of completeness I'll describe what they made me do over the phone the first time in case anyone knows what it was about: Power down. Remove all plugs. Remove battery. With battery out, hold down Power button for 5 seconds or so. Re-assemble. Re start. As it starts up hold down R key, P key and I think it was ctrl and cmd. Let it bong three times. Let go of keys and let it start up. Fix permissions three times. Verify permissions once. Was he just making me do the Hokey Cokey or was there a reason that might indicate what's possibly wrong with my screen if I knew what it was? Thanks chaps.