Help with playback stutter in Sony Vegas Pro 11 I've got 2 DSLRs in my kit, a Nikon D7000 and a Nikon D3S, for 1080i and 720p respectively. I experienced stuttering playback with footage from both cameras, and figured it was something with Nikon's codec until I had the same issue with HDV footage from a Sony camera (client was unsure of the model#). I recently upgraded from Vegas 8 to Vegas 11 to handle HD footage more cleanly. My machine has 6gb RAM, one of the recommended NVidia graphics cards, and my CPU, while slower than I'd like at 2.53GHHz, is still within recommended ranges for Vegas 11. My internal discs are spinning @ 7200RPM &amp; I'm running Win7 Pro. I've downloaded all the latest drivers, codecs and updates that I could find for my hardware and software.

So here's more detail on what I've tried:
Playback in Vegas 11 Pro stutters for both the Nikon and and Sony HD footage. 
SD footage plays back just fine. 
Only picture stutters, not sound. 
Stutter happens at all playback resolutions, from draft to highest quality. 
If I view the clips in an external player (Quicktime, VLC, DivX) playback is fine.
If I render out a clip to Quicktime, AVI, Windows Media, MPG2, MPG4 at HD resolution, or at least matching the camera clip as closest as I can, I can pull it back into Vegas and play it without any issues. 

Based on the above facts:
It's appears to be a Vegas issue, and since playback after rendering THROUGH Vegas works fine, I suspect it's an issue with the Nikon codecs on the inbound side. But, what's up with the Sony playback stuttering? Maybe it's hard drive speed issue? Then why do rendered clips, some of which are larger than the original, not stutter?

I never did any setup from within Vegas to point it to the GPU. I assume that Vegas will FIND my GPU and assign whatever processes as it sees fit. DO I need to do something special?

Has anyone else had success with Nikon clips, and would you be willing to share your setup parameters?

Thanks.
I have seen some trainwrecks by combining Nikon .mov with Vegas Pro 10. After tech calls into both Nikon and Sony it was determined that my machine didn't have enough resources.

I need to upgrade from 32 bit to a 64 bit version of Win7, plus I need to go from a quad core to an i7, and from 4GB to 12 GB or better. I can use my Nikon files now but only if I keep the total under 1 GB, short projects only but it works. One thing that may help your stuttered preview is to set the window to preview mode at 1/4 size, this helped a lot for me.

Here is a tutorial that covers everything I've tried and more of the things that may help you
get your playback smoother.