Happy New year,
We have a RSD site (see www.fabrikits.co.uk) which is OK on tablets and smart phones. But when extended on 16x9 large screens there is too much bright white to the left or right. If we change the background colour on all rows to grey it extends to the edges like the white. The original had a pixel perfect framed pages,
(see http://www.fabrikits.co.uk/motorhome_for_hire.html )
which gave the pages definition and stopped the eye from wandering into the great white world.
Any ideas on giving whole pages a boundary?

M J Berkin, I like the way your site looks and do not see the white as a problem, but you could use a gradient as I did on my site...

http://www.workhorsepainting.com/

On my site I had a white background but prefer the look of the gradient for the background.

Beige?

You can put a border around the grid

You could of course try a subtle background colour or boundary (beige, light grey...) But first I would make the text the same width at the images above it, that might take away some of the feeling of viewport being too wide. If it doesn't ruin the image quality, you could even make them and the whole content area wider.