And also 2 cards below 1.5 gb vram

Just ran clod again on highest settings with single gpu at about 50 fps average, but saw a vram reduction to my last (but very old) tests. It uses up to 1.8gb vram at normal 1080p.
So, a card like Ricks 450 with 1gb woill definetly have troubles. 1gb is too less, even 1.5 of the standard 680.
Note, that some of the biggest stutters occur with the streaming. I did with my i7 920 @ 4 ghz and ssd. Some stutters are simply not avoidable on some system configs. So, I will need to think about a better cpu to reduce it, although my cpu is running sufficiently for clod. I am not at its performance bottleneck...
So, rick, if you want to get rid of vram stutters, u will have to tweak texture load down to 1gb vram usage. That.means reducing texture quality