My monitor blew, and I got a new HD one at Costco. With the standard Debian nouveau driver, it does the 1 inch underscan thing automatically. That means I get a black border around my desktop. It is impossible to fix this! If I use the binary nvidia blob I can probably do it.
My Xbmc setup has over-underscan sliders so it works well for the big tv. So for the monitor, right now it is best to buy a monitor a bit bigger than you need. :(