I have a system with and Asutek P8H61 M'board, with onboard audio and a Radeon HD 6450 with DVI, VGA and HDMI out which includes HDMI audio. I installed ubuntu (64bit) 12.04
I believe when I installed ubuntu I tried the restricted driver but it failed dismally and it was quite difficult to set it back to the opensource driver. I had to use the terminal but I forget what I had to do.
Since then it has been working perfectly. I have two monitors and I have them working side-by-side, one connected by DVI cable and one by VGA.
All worked perfectly until the kernel update 3.2.0-33-generic #50-Ubuntu SMP.
The video stopped allowing two monitors. The VGA monitor would flash with random noise. Sometimes parts of a possible screen would be visible, mostly in the top half of the monitor usually flashing and distorted.
The Monitor connected by DVI cable worked fine. With each successive kernel upgrade the situation stayed the same. I discovered that if I booted into 3.2.0-31-generic #50-Ubuntu SMP I could get my two monitors back and everything was OK.
Then when the last kernel upgrade came, Linux 3.2.0-37-generic I have two issues:
1. Now when I try to boot into any kernel later than 220.127.116.11 I get text mode with no graphics at all.
2.The other issue is much more of a hassle. When I play a movie, say an avi or youtube I get sound but no voice. I assume that the headphones are connected to the rear streams of 4, 4.1, 5, 5.1 audio with the front possibly going to the HDMI output which I'm not using. It is very frustrating. No amount of using sound configuring utilities seems to help. All the forum posts seem to be about people who want 5.1 audio but I want the opposite, just normal stereo and just normal headphones or speakers.
I hope someone may be able to help me.