Dual monitors-ATI and fglrx

[Luke Kuhn]

The multimonitor situation for AMD/ATI uers is like this: If you use the open source ATI/Radeon (gallium) driver, no problems, everything "just works." This sort of open source support is why I use ATI/AMD and not Nvidia cards. The only problem is that (as exepcted) opengl rendering of Blender projects is a bit slow, although still about 4x faster than CPU rendering on AMD Phenom II x4, so what am I complaining about?
The fglrx driver (in precise, anyway) now works in gnome-shell and is suppposed to support Xrandr, but doesn't support it very well. I get the usual Xrandr/fglrx bug of not being able to move the secodary monitor out of the primary monitor, that is being restricted to cloning or partially cloning the primary monitor. A secondaery montor inside the primary monitor NOT cloning it is an ugly mess with any driver. Trying to set up two monitors in the Catayst Control Center is worse-you can set it up easily enough, have to restart X to put it into effect-and then gnome-shell crashes, other window managers will work. With my card, a radeon HD 5570, the secondary monitor simpy goes all-grey, displaying nothing else with any window manager except that during an attempt to start gnome-shell it may flicker to the color of the background image. 
The only reason with my workflow to ever run fglrx is for fast Blender rendering using openGL, in almost real time. This is a factor for my "Fur Wars" and similr videos that start with a modified Star Wars crawl made in Blender, but a minor one. I put fglrx on a backup partition, can uise it if I need to experiment with something in Blender and render multiple times.
At the moment, I cannot switch between two monitors (for video editing, open-source driver) and real-time openGL rendering for Blender 3D content creation(fglrx driver) from scratch without rebooting. Maybe some way to run both drivers in UMS and toggle xorg.cof files?
The modified Star Wars crawl in 1024x600 resolution  is the benchmark I am using for comparing drivers in Blender. 		 	   		  
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