Remember when Linus Torvalds lambasted NVidia for not supporting their Optimus technology in their Linux drivers for half a decade and counting? Well, I went out and bought an AMD/ATi video card as mu upgrade. And you know what? Its Linux drivers are far, far worse than NVidia.
1. Most of the games I had working fine on NVidia, do not work on AMD. And those that do suffer far more visual corruption, synchronization bugs (like bottom 40% of the screen rendering half a second after the top 60%), strange visual artifacts (weird triangles popping out of everywhere) and crashes, lots of crashes.
2. There were crashes with NVidia too, but NVidia never managed to crash Compiz along with it or crash the whole X server or lock up the system so far that only SysRq works or even lock up the system so far that only powering it off manually works.
3. And then there is the configuration atrocity. Apparently AMD is too good to store its configuration in /etc/X11/xorg.conf. Or even to document the supported options there. Instead they have their own (also undocumented) configuration file in /etc/ati folder. And it is undocumented because it is a cryptic mess and the only supported way to change it is to use their tools - aticonfig and amdccccle. The command line tool is almost reasonable, except it is also barely documented. For example, one of my screens somehow was always stared at 1920x1080@30Hz. There were 3 different ways to specify default resolution, but none of them used or saved the refresh rate. And when I changed it in the GUI tool - the refresh rate did change, but it was never saved. Oh there nowhere is a save button. It 'just works', except when it doesn't. Like: both of my screens for some reason started with huge black borders around the screen, I finally narrowed it down to the GUI setting "overscan" which defaulted to 10%. Ok, so I change it, it works, but next time I reboot, the overscan is back! I had to find an undocumented invocation of the aticonfig that would change the default value to 0%. Why did this one setting not save? Oh and fun note - the refresh rate of that second screen was correct on the login screen, but it then swiched back as I logged in. Fun, huh?
4. Even at basic desktop tasks fglrx if inferior to not only the free driver, but also to the nvidia driver - even simple scrolling of a large folder in nautilus seems to tax the 200$ card to its limits - the bottom row blinks into place almost half a second after I stop scrolling. Another example - with NVidia when I switch my TV to the HDMI input from the card, the sound starts at the same moment as the picture, however with AMD the sound only decides to show up 10-15 seconds later. And sometime it does not show up at all, unless I start the AMD Control GUI tool and only then the sound shows up 15 seconds later (without doing anything in the GUI).
It may be that one part of AMD is better than NVidia at talking to free driver developers, but another part is so much worse at actual technical work of writing a driver, it is not even funny. They are busy reinventing the bycicle of configuration and display management, while their core driver is just ... not good enough.
TL/DR: Anyone wanna buy a HD 6850 cheaply off my hands?
Crossposted to Google+ - https://plus.google.com/u/0/107099528362923100900/posts/6PC7RFQpm8K
P.S. I also noticed the color difference - with NVidia there was no difference between colors on my LCD TV and my IPS monitor, but with AMD there is a huge difference, the TV color just got washed out. I guess there is no proper color calibration support in the AMD driver?
Update: I have managed to return the HD 6850 to the shop where I got it from (thanks to a nice law requiring web shops to take stuff back within 14 days no questions asked) and got the new NVidia GeForce GTX 660 instead. I had to build an updated NVidia driver (304.48 from this post, just like here or here) but other than that it was smooth and painless and everything is working great again. Only even faster :)