2nd ATI Video Card not usable

[tux_fan]

I have two video cards that I would like to use. Only one of them is being recognized. I have 2 monitors on one card and another monitor on the other. I am currently only able to use one. I don't have a xorg.conf, as I understand they are thing of the past. I attempted to install the ATI/AMD driver, but that did help. The card is being recognized by the system, but not being used. Is this a limitation of Mint, or possibly Cinnamon? Do I need to create a file for /usr/share/X11/xorg.conf.d/ ? If so, is there a way to get a hold of the information the system is currently using so that I can simply add the extra Screen?

Here is what we are working with:
Linux $hostname 3.5.0-23-generic #35-Ubuntu SMP Thu Jan 24 13:15:40 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
Linux Mint 14 Nadia
Cinnamon 1.6.7+nadia

% lspci | grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Cedar PRO [Radeon HD 5450/6350]
02:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI RV710 [Radeon HD 4350]
% xrandr | grep Screen
Screen 0: minimum 320 x 200, current 2384 x 768, maximum 8192 x 8192

[zerozero]

disclaimer: i don't have amd/ati

amd dropped support for the 2xxx-4xxx series cards so basically you have an unsupported and a supported card; if you install the prop. drivers it will only "see" the newer card.

(there is now a legacy driver that apparently works but it will only be effective for your older card)

the only option (as i see it) is the open-source driver but i don't know if it will support the conf. you want (2 cards-3 monitors)