Ok this problem has been present for quite a while. I upgraded my graphics card to the ATI 4870 a while back. I have a 2006 MacPro, 2.66ghz dual x2. In final cut pro when playing back footage, this flashes over my edit. It shows up every couple frames or so and never static. It's always changing, sometimes into different colors especially if I add an effect on a clip. Sometimes it seems like a restart fixes things, but it's touchy so if I add an effect bam it comes back then it won't go away. It's not just a Quicktime issue, because when I scrub across an empty sequence I get it again. Also, I don't just see this kind of thing in FCP I see it sometimes when playing back QT files. I've also seen it on my desktop sometimes static or in other random places. Also, Adobe Premiere has NO issues with any playback and neither does After Effects. It seems to be Final Cut Pro ONLY and Quicktime ONLY (when it comes to editing). Why is my system having so many issues with this card? There's been part of me that's ready to simply give up on the system and get another and just use it as a rendering farm...but maybe there's something after all this time that's alluded me? By the way the card still has worked great despite this, and I've edited my entire feature film with it in my systems. Renders 99% of the time come out fine...it's just an on/off thing. My system is up to date and I recently got Final Cut Studio 3 hoping it was a compatibility issue or something, but the problem persists. Thoughts?