i see in the readmes for version 4, i need an nvidia 7300, looking at buying 2 older Mac Pros (cost for particular job is a concern), but can't find them with the right video card...and the 7300s are hard to find...are there any other video cards that will work with the Media Composer?  i know the Avid side is very set on specs, but have found Macs to be a little more forgiving...thanks in advance