I've tested Ubuntu 12.04 and latest F17 nightly build. After selecting kernel in GRUB, the monitor simply turns off because there is no signal. I've tried with both D-Sub and HDMI outputs. I can attach any logs you need.
So, does 'Kernel Version: >3.2' and 'Regression: Yes' mean this worked with 3.2 kernels but is broken with newer ones? If so, can you bisect? Please attach the dmesg output corresponding to the problem.
Sorry, my mistake, I meant >=3.2 I wrote "3.2" because 12.04 has 3.2 kernel. There is one confusing thing: the driver works well now in Fedora 16 with the latest 3.3.4 kernel.
Okay, I finally discovered what is going on here. First of all, now this bug seems to be reproducible only with D-Sub output. My motherboard is ASRock A75M, monitor is LG E2360. Everything works very well (and with a good hardware acceleration) on all kernel versions if I connect my monitor with an HDMI cable. If I connect it with D-Sub cable: Bug is reproducible with: default 12.04 LTS kernel, and with 3.3.0; it is NOT reproducible on the latest 3.3.4. So, with the latest 3.3.4 kernel I have a good hardware acceleration without having to boot with nomodeset. Though this problem seems to be solved in latest stable kernel, I attach the /var/log/messages file I copied from hard drive with F17 with 3.3.0 kernel, just after encountering this bug. Sorry for my English.
Created attachment 73264 [details] /var/log/messages
You need this kernel patch to get VGA ports with DP bridges working: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=700698e7c303f5095107c62a81872c2c3dad1702