So I just got a 3.0Ghz 8 core Mac Daddy thinking finally I'll be able to cut the 2K QT proxy files as an offline.. but no, even with all this horsepower no dice, it still judders. Adding insult to injury I can't even playback the "M" proxy without some drops. So what's the deal here, is it the video card? I went with the ATI for the time being, until I know the Nvidia driver issues are worked out. I downgraded QT to 7.3.1, I'm playing the material off a 3G E-SATA drive? I've got like 10GB of RAM too. What will it take to playback the 2K proxy in real time?