I am looking to upgrade to Windows 7 64 bit running Vegas 8.1 on an I7 860. I know that the 32 bit version uses only 2 Gig of RAM. With the extended size of the operating system and application, what would be an acceptable amount of RAM to utilize the benefit of a 64 bit system?
I have read a lot of complaints about Vegas 9, so that is why I am resistant to upgrade to Vegas 9. Should I move to 8.1?

This system never touches the internet. It is for Vegas editing and DVD Architect only.

With 8.1, I could not print to DV tape. It seemed to edit fine but I had some rendering issues and could not output to my deck. When 9.0-64bit came out, I tried it and it both rendered fine and would output to my deck fine. 9.0 seems much more stable than 8.1 on the 64-bit side.

Personally, 9.0 has simply worked for what I do. Yes, I know some people have had some issues with it but can only say I've not seen those issues.

Edward,

I do not have to print to DV tape, only DVD using DVD Architect. I edit standard DV, HD, and AVCHD(Cineform conversion) The AVCHD rendering is what forced my hand to upgrade, as it takes so long. As I see dual and Triple channel memory, I don't know how much memory is used for overhead in a 64 bit operating system and how much will be used by Vegas.

My 64-bit machine has 4 Gig. But memory is so cheap it won't hurt to get more.