Multi-camera - lower resolution preview as references?

Hi all.

Can I make a multi-camera sequence using lower resolution previews as reference, like older versions of Premiere Pro used to do? How can I do that?

I'm using Premiere Pro CC7, and when I play 9 cameras fullHD together in multi-camera mode, my quad i7 Mac Mini 2,3 runs out of CPU. If I could use 960x540 instead, or even 640x320, it certainly would fix the problem.

Thanx,

R.C.Ballerini