The empty div tags used to hold <img> tags for positioning. In the style sheet I now use background-image: url('pic'). Having removed the <img> I assemed the div element would still have to be somewhere in the document. Would <div class="bgpic" /> alone be sufficent?
I reckon it looks at the big resolution but it's true it's a bit big for 800x600.
Thanks for the input...