DXVA and AMD 785G chipset problems

[chapas]

Hello people.

My HTPC is having problems with its DXVA decoding of 1080p h264 content.

I have proper DXVA decoding randomly. Sometimes the machine starts fine, but when I reboot for some reason I can't play any 1080p h264 file, not even with software! For some strange reason MPC-HC shows DXVA enabled but the videos stutter heavily. All videos present this problem. And then I reboot again and suddenly everything works fine.

Config is:
Biostar TA785GE 128M 6.0 (ATI HD4200 integrated, with 640MB memory, sideport + system)
AMD Athlon X2 240
4GB DDR2

Hopefully someone has a similar system and knows how to fix this.

Thank you!

[Sharktooth]

have you tried updating the chipset/video drivers?

[chapas]

Yes. I'm on the latest version on both, Southbridge (10.9) and Video (10.9a).

I can't get what's changing, since I just have to reboot to fix it, but it's not a real fix.

[ranpha]

Disable the sideport RAM and use system memory exclusively.

[chapas]

Hi ranpha. I just tried disabling sideport RAM.

I had proper DXVA for the first 2 boots. The third was broken again :(

Thanks anyway! I'm open to try any other fix.

[chapas]

Ok, I got more info for troubleshooting. I captured the screen showing the information by MPC-HC's Display Stats:

http://img513.imageshack.us/img513/1873/snapshoto.th.png (http://img513.imageshack.us/i/snapshoto.png/)


In this screenshot playback is fine, but I noticed that when DXVA is somehow broken, the upper right "Clock" gets as low as 30%.

Is this useful?

EDIT: MPC-HC build is: mpc-homecinema.1.4.2689_(x86)_msvc2010

[yetanotherid]

Maybe instead of using MPC-HC, try ffdshow for DXVA playback.

Try installing the latest version of the Combined Community Codec Pack (it's basically MPC-HC & ffdshow), let it disable anything it wants to disable as it installs and select the DXVA option at the settings screen during installation.

If that works try enabling DXVA in MPC-HC again, if you want to, to see if the problem returns.