Changing settings for a video card in ubuntu

A helpful command to remember is, from the shell: dpkg-reconfigure xserver-xorg. I used this today to fix this problem. Ubuntu would not give me the choice of a higher resolution for a new monitor I used. I ran this command, using mostly default answers, and then when it asked about the available resolutions, I checked the ones I needed.

Earlier, on a different machine, I needed to install drivers for a new ATI Radeon 9550, and this worked.

sudo apt-get update
sudo apt-get install linux-restricted-modules-$(uname -r) #Okay if it is already installed
sudo apt-get install xorg-driver-fglrx
sudo depmod -a
sudo aticonfig --initial
sudo aticonfig --overlay-type=Xv

I did not try this interesting page:

https://help.ubuntu.com/community/BinaryDriverHowto/ATI