Re: Problem with video acceleration, xv support messed up or insufficient card?
This is getting tough.
VDPAU actually makes HD video on the 30" display on the non-primary graphics card work. Unfortunately there is trouble. On this particular machine performance with xv is better than vdpau. I have about 67% CPU for mplayer with vdpau and things are not entirely smooth. Worse, ending mplayer with Control-C just lead to a bus hang (X11 hangs, network shells continued to work until they tried to do disk I/O). Finally, although vdpau seems to work on the second adapter it refuses to work on the primary adapter. That would be all fine with vdpau for the 30" and xv for the 24" inch but alas vdpau isn't smooth and xv is.
I now made the 30" display the :<x>.0 display and declared it's adapter the primary adapter in the BIOS, but still a call to xvinfo reveals that as far as xv is concerned the gtx7800 is still the primary card. So still no xv for the 30" display. I suppose to actually exchange this I'd have to exchange the physical slot of the PCIe video cards.
Sadly, using x11 as the video driver works fine, but of course now I lost scaling support.
mplayer has a -vo xv: port=<x> option but I tried every one of the 32 ports on the card I want and it always fails to get that port, presumably because now I'm on the wrong adapter (or adaptor as xvinfo calls it). The xv:adapter=<x> option seems to be DirectX only and I confirmed it doesn't work.
Still looking for ideas out of this mess. What could possibly be wrong with the dual-link port on the 7800GTX?