FOSS support for Radeon HD 3200 (780G)

[Slim Joe]

Google sends me into a time warp when I search for info about Xorg
support for the Radeon HD 3200 (AMD 780G) using the default
opensource driver. All the posts and articles I've read focus on
the use of the binary fglrx driver. Is the binary driver still necessary
to get decent 3D?

What's the status of support for the RS780? Will it work out of the
box in Intrepid Ibex (which I accidentally discovered recently could do
without the infamous xorg.conf)? Also, what frame rates (FPS) should
I expect for 3D games like Sauerbraten or any of the free Quake
spinoffs?