Setting PAL widescreen HDMI output in Linux
To set full-screen PAL widescreen 16:9 HDMI output you can simply use this command (as root):
# xrandr --output HDMI1 --mode 720x576 --rate 50i
Obviously the 720x576@50 mode must be legal for your monitor. Usually TVs list it in EDID data, while PC monitors often don't support this resolution.