Thanks Mike!

I have done it before, but it also happened that the rendering video had some errors in it, but that was with older versions of Vegas I think...

Marcel

I've been doing that for over a decade.

I noticed on Win 8.1 (never tried it on 7) that when you run a second instance from metro you need to use the "run in new window" option. If you don't it goes to the currently running instance.

Either right click on the tile in metro or touch and hold to get the options in the bottom of the window.

I normally run multiple instances of Blender & Vegas so I encountered this feature early on (which makes sense: most programs only allow one instance at a time & you it will prevent you from running a dozen calander/ie/whatever apps).

...and of course the first project will be sucking up most, if not all, of your machine's horsepower. So I run the rendering instance at "idle" priority. I still have the appearance of quick response, yet the render proceeds when nothing else is happening, which is a surprising percentage of the time.

1st launched window of vegas will be the only window with GPU accelleration, 2nd+ windows will be CPU only. Recommend 16-32GB RAM to keep from swapping if your projects are large.

Go to Task Manger - details and set the process priority to low so you can edit in the 1nd window. Recommend closing the background render project, and opening that project as 2nd low priority window so main edit window is gpu enabled at normal priority.

I just change the affinity to the desired # of cores I want each instance to have. You get more control over what happens vs the priority. Plus you can guarantee the max amount of CPU power per instance. I've NEVER had any issues when doing this.

I started doing this on Vegas 4 & I do pretty complex projects, I've never noticed RAM to be an issue even with Win 2k/XP 32-bit.

Instead of doing all this complex close/open instance of Vegas, just open a second one & render from there. :)