If a slide show is configured to rotate through many slides, each refresh/rotation takes up more RAM for the browser. Over time, the box/browser will fall over due to low memory.
For example, a screen with 9 graphs on it takes roughly 5MB RAM up on each refresh.
The memory never seems to be given back unless you do a manual refresh of the page. As soon as you do a manual refresh, the browser returns to normal memory usage.
This doesn't seem to affect Screen refreshes, just slide shows.