2011 15" MBP: 2.2GHz, HR AG, 128GB SSD. I noticed this the other day while moving around windows. If the 6750 graphic card is in use, it will make the top of windows experience this kind of tearing/trailing effect. I'm not sure if this is a defect in just my machine or a widespread glitch. Anyone care to try this out and confirm? To replicate: Turn off Automatic graphics switching and grab your window and move it around at the top of the screen. For me, it only happens at the very top of the screen (around the toolbar/bookmarks bar area in safari for example). The faster you move the window, the worse it gets. It's something that's really hard to capture on camera so you'll just have to replicate the circumstances and see if you notice the symptoms I'm mentioning. Notice the glitch only happens at the very top of the screen. You'll see me shift the window down and move it around but the glitch will stay at the top of the screen. http://www.youtube.com/watch?v=XYC4MG_nn44 I'm not sure what could be to blame here. Graphics card drivers? The card itself? It seems that the issue gets worse under load. I mean, when you are on a site like youtube watching videos, the glitch is pretty bad. Whereas if you are on google's homepage, the issue is barely noticeable. I am running the most up to date software (10.6.7 update that came out yesterday). Thank you for any help.