Preview not smooth - my fault?
 

I'm using Cineform (High Quality Mode) to convert AVCHD/H.264 files and editing in Vegas on a Q6600/8GB in Win7/64. Preview seems as if it should be a lot better than it is - slow, jumpy, delayed, etc.

My project setting are DV Widescreen, 8-Bit.

Am I doing something wrong? Shouldn't it work much better than this?

Paul, if you're using Pro 9, do you have the Adjust Size and Quality for Optimal Playback option in the Preview window (right-click there to get to this) disabled and set to your normal setting (typically Preview/Auto)?

Mike, are you saying I should disable Adjust Size and Quality for Optimal Playback?

Paul, that was one of the first things I changed when I got Pro 9.
The main reason is that I didn't want the computer deciding what frame rate it would play at.
I generally leave mine at Preview/Auto unless I'm doing a RAM render or a Prerender in which case I'll set it to Best/Full.

Do you know of any other tweaks that might help? My footage is 1920x1080, but I have the project set to DV. Does that matter at all, or does it only effect rendering?

Slip a core i7 under the hood... I didn't have too much luck with AVCHD with a Q6600 even at fairly low settings - draft/full was about the best I could achieve. Although I'm getting decent results with a more recent quad core laptop... may have been a bottleneck elsewhere in my old desktop...

Paul, could you be using too many threads? I believe Vegas comes configured for 16 threads out of the box, while you should be using the number of processors you have plus one. Using too many threads may impose unnecessary overhead, so Windows cannot handle the playback at full speed and starts dropping frames, which in turn causes jerky preview.

Though I am not sure whether it uses all those threads when previewing or only when rendering, so I may be completely wrong here.

Dave - If it was just a matter of replaceing the CPU, I'd do it immediately. Unfortunately, the i7 would require a new motherboard, new memory and a new power supply.

Adam - I will give that a try. How about Preview Memory? What's your recommendation there?

The way I understand it, you should keep it fairly low. It is the amount of memory Vegas will allocate at the beginning and only release when it quits. So, if you set it too high, you are wasting memory that can be used for other things. If you set it low, it will just allocate whatever memory it needs when it needs it and release it when it no longer needs it.

So, in theory, if you go too low, it does not hurt as it will allocate the needed memory anyway, but if you go too high, you get a performance hit.