I am a long time Linux/Nvidia user and have been enjoying vdpau on my desktop for years However i have recently build a HTPC with a Asus E35M1-M PRO mainboard featuring a AMD E-350 APU (1,6 GHz dual core CPU and Radeon HD 6310 graphics card. Having heard that the catalyst driver has catched up to nvidia in recent days, i thougt i'd give AMD a try.
I am running a current Arch Linux with MythTV 0.24.1 and the proprietary catalyst driver from AUR. My window manager is fluxbox and i don't use composite 3D-desktop stuff or whatever it's called currently. Catalyst seems to run the way it's supposed to run, direct rendering is working.
Unfortunately even the standard 720x576 MPEG2 DVB-C doesn't run smooth and seems to be lagging behind and loosing frames (plus the ATI standard tearing ). This is the case for XVideo and OpenGL. XVmC doesn't work and VDPAU obviously does neither. The cpu load is at roughly 70-80% on both cores (< 10% on nvidia even without VDPAU!!!).
I am suspecting i am missing some essential "ATI magic" in xorg.conf or with ati-config to get XV to work in a acceptable way. Does anybody have some pointers?