What signfigance does a video card play in rendering times from programs like Vegas, Avid, and Pinnacle?

Can a system with a great processor and high ram still render video slowly if the graphics/video card is bad?

With Vegas, the video card play 0% in the rendering. Some other NLE's do use the video card to assist process. Plus there are some plugins in Vegas that will use the Video card.

Playback while in Vegas really needs speed. 3.8ghz CPU for example. A fast dual core will help you obtain that. For batch render quad core is the way to go for speed.
The new Intel I7 is a fast CPU. I believe it has a larger amount of on board cache. You would have to investigate that for more details as I don't own one and haven't researched them.

Do you have any idea why I'm getting such slow rendering times then?

Rather than re-explain everything, if you click that board link you'll get the jist of my problem. Any help would be appreicated.

http://www.dvinfo.net/conf/what-happens-vegas/137799-render-time-differences-vegas-8-1-vs-8-0c.html#post1019860

Thanks