I've moved to ubuntu from windows 7. In W7 I had 3 monitors on 2 graphic cards. 2 monitors work from ati card and 1 from intel card. In ubuntu I can't make it to work like before. Now works only 2 monitors from ati card. But I can switch to intel graphic monitor by pressing ctrl+alt+f6 (so it works).

lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation 4 Series Chipset Integrated Graphics Controller (rev 03)
01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI RV710 [Radeon HD 4350]