I tried fresh install 4 times on each Ubuntu 12.10 and Linux Mint 14 Cinnamon (both 64bits) I tried several methods, through:
sudo apt-get install fglrx
Also
sudo apt-get install fglrx-updates
Also generating the deb packages, and running it.
Also downloaded the ati drivers and executed that .run file (all through commands, cant remember them).
Also Using Jockey, synaptic packet manager, ubuntu software center, ppa's. None worked. Every time after the installations were sucessful i did reboot (so changes would take place), and for my surprise, monitor was out of range. Though by entering tty1-tty6 allowed me to use CLI (that text-mode user), using that i stopped xserver, mdm, and changed xorg.conf or xserver, something hmm i guess was /X11/xorg.conf ? Gone there, Monitor section, add something MODE (some tutorial told me to), and added the frequency range my computer could support, both horizontal and vertical. After rebooting, the error kept on.
And every tyime i uninstalled the current Radeon drivers (Gallium 0.4). The drivers i tried to install were 12.4. 12.6, 13.1 beta (i guess). Those were lots of things i tried to do.
Btw, people told me that when using pre-installed ATI drivers, their monitor could already use the apropriate screen resolution. Why can't i use 1600x900 on a 21"5 computer? Screen doesn't look like on my netbook, which run it's c-60 graphical cards (also using proprietary drivers) just fine.
Should i do a fresh install of a lower version of Linux? for instance 11.04 Natty, 11.10 Oneiric, Kubuntu 12.04LTS or Linux Mint 13?
Running xrandr (or something like that) shows that my monitor can handle up to 8K x 8K resolution, and 60Hz. So it should be running it.
Sorry for unorganized text.