I have Atom N455 with Intel GMA 3150 and Debian 6 xfce x64. It's connected to 1680x1050 display by VGA cable. The problem is that the screen looks blurry (on Win also). I found that the maximum resolution supported by this integrated graphics is 1400x1050. So, I want to make it clear, how to turn off screen auto scaling to achieve 1400x1050 visible area on display.