Dear forum-ers, I've been seeing an odd disturbance on my MBP's screen which I've not seen reported by anyone else (yet)! I've got a late 2008 MBP 2.4Ghz upgraded to 4Gb memory which I bought in Jan '09. I'd posted on the Apple discussion forums some while ago but I've had no joy there so here's a summary of the relevant posts. I'd be really grateful for any advice people may have. ---- The issue I have is that, although under all other conditions it performs perfectly, when there's a lot happening on screen such as a fast moving video or playing a 3d accelerated game such as Quake 4 or using multitouch to quickly scroll a window up and down, the screen seems to get updated in roughly four horizontal chunks. You can see there's a split-second delay between consecutive chunks. This happens when using both the 9400 and the 9600 chipsets. My barometer for this has been running Quake 4 and you can see all through the intro movies that there's a strip about an inch high running along the middle of the screen that tends to lag behind everything else when there's a lot of stuff happening on screen. I tried running Q4 in windowed mode with Activity Monitor running but it's not even putting a 50% load on the CPU (which you'd hope given the age of Q4...) and this problem doesn't seem to occur with pure video content - DVDs or iTunes movies for example. I did notice that it was a lot less noticable in windowed mode than stretched onto full screen. Could it be a scaling issue given that the Q4 demo wants to run 800x600 and the MBP screen is 1440x900? Or could it be a problem with the fact that Q4 is 32 bit and I'm running OSX in 64 bit? Or is it time for a trip to the Genius bar? Is this standard behaviour and I'm just being picky or is this a sign of something going wrong with the hardware? I'm running Snow Leopard 10.6.3 with all the latest updates including the EFI update. ---- A bit more info... it also happens during the "id", "Raven" and "Activision" movies while the game is loading. I've been experimenting with using screen capture software and QuickTime to record these blips when they happen but they don't show up in the recorded movie files... ---- So I spent the day playing Quake 4 and I have to say that on maxed out quality settings it didn't drop below 60fps so it's not really straining the graphics card and yet this glitch was showing up on a regular basis and at varying heights on the screen. I managed to reproduce the glitch in Burning Monkey Solitaire which you can see in this youtube video which I captured by pointing my digital camera at the screen: http://www.youtube.com/watch?v=PCyUaN24tFM Watch the 7 of diamonds as it moves across the screen... the bottom half of the card moves at a different rate to the top half of the card. The 7 of spades does the same thing as it moves for the second time. Again, attempting to get a video of this using a screengrabber didn't work which makes me think that either my screen or logic board is screwed. Anybody got any ideas? Thanks!