Dual Monitor/Xinerama not working; cannot even detect on-board graphic card
- by Steven H
I have Kubuntu 12.04 and two identical VGA monitors. One I plugged via DVI-VGA adapter into the DVI port of my discrete AMD Radeon HD 6670, the other into the VGA port of my on-board graphic card (Radeon HD 6410D).
After installing Kubuntu I got a black screen, so I booted with nomodeset and installed AMD's catalyst drivers but only the monitor plugged into the discrete graphic card worked.
Using lspci I saw that the on-board graphics was not listed. Then I found in the BIOS settings the options "Surround View" and "Onboard Dual Link DVI" both disabled. After enabling both, the on-board graphics card shows up in lspci but in amdcccle, it only shows as [Uknown display]Uknown adapter.
When I try to enable xinerama, I get a black screen after rebooting on both monitors. I tried several options and hints from the web but nothing worked so far. I also reinstalled the AMD drivers several times.
What should I do?