Before you read: I have recently installed Snow Leopard and a new 4870HD (Mac version, not flashed or anything) on my MacPro (2.66 Gen from 2007). Bear in mind things have been perfectly fine for weeks until this morning...so it's not a straight up "it's not compatible" answer. Ok this scared me to death earlier but I'm pleased to report that I know it's not my footage being corrupted. I opened FcP this morning and hit the playback button...and found this: At first my heart sank because I thought "my files are screwed up." Even playing them back in QT yielded the same result...but after a restart the problem was gone, that is until tonight when I'm posting this. It's back...and I have no clue what it is. It could be anything from a strictly final cut issue, quicktime issue, graphics card, I don't know. What do you all think? The fact that it's not consistent is what confuses me. I opened up FCP before deciding to post this, began going through a sequence, and things were good until I brought my scrubber back to 1 and played again...then they showed up. I just set my playback to carry over to my second monitor, magically all the weird digital things are gone...but after a minute or so of playback they showed up again. I'm almost certain it's my GPU because the digital chunks show up OVER the Widescreen filter on my footage, if it was my source files or quicktime, I think they would end up only on the footage itself not the black matte.