Problem with 9800GT and VDPAU

jyavenard · 05-27-09, 03:30 AM

Hi

Trying to help someone getting his 9800GT to work with VDPAU.

And I haven't had much luck..

I've identified the issue to be related to the speed the card is running at.
GPU is at 300Mhz by default and Video RAM is at 100MHz

In the default mode, H264 720p video decoding is very sketchy in MythTV, 1080i is even worse.

Running glxinfo at the same time, change the speed to 600MHz / 900MHz and at that speed, playback with VDPAU is fine...

Now, the problem is that as soon as I stop glxinfo, the clock goes back to 300 / 100Mhz...

Video drivers is 180.60.

Any ideas on a work around ?

Thank you
Jean-Yves

thefirstm · 05-27-09, 04:07 AM

There was another thread about this a while back. The devs said they were looking into a fix, but I haven't read anything else. I do have a recommendation, though. If possible, try disabling Composite by adding this:

Section "Extensions"
Option "Composite" "disable"
EndSection

to the xorg .conf. This is a dirty workaround, but evidently the overlay output method (used when Composite is off) is much less GPU-intensive than the Blit output method (used when it is on.) This workaround does not affect the clock-speed of the GPU, but it does enable my 8600m GT to decode SD MPEG2 or H264 video smoothly. I will test HD in a minute.

jyavenard · 05-27-09, 04:18 AM

Disabling Composite has nothing to do with my problem.

First, composite is already disabled and second, disabling composite is only required to prevent tearing.

The issue I'm reporting here is that the nvidia GPU is set at a too low frequency and running VDPAU doesn't raise the clock speed sufficiently.

I've played with some settings like:
Option "RegistryDwords" "PowerMizerLevelAC=0x1"

in the device section, it does start playing properly.. But after a few minutes, video playback becomes choppy again...
The speed of the video card becomes 600 (GPU) / 900Mhz (RAM) with the 0x1 settings

thefirstm · 05-27-09, 04:33 AM

Have you tried the latest beta driver version? This might help the issue as well.

jyavenard · 05-27-09, 05:25 AM

I just tried with the latest beta 185.18.10

It is a tad better, but after about 2 minutes , it becomes all jerky again ...

**Stephen Warren** · 05-27-09, 11:08 AM

This is probably a known issue with PowerMizer. We believe we've fixed it, and should be in a driver fairly soon.

jyavenard · 05-27-09, 09:21 PM

Does the new 185.18.14 RC drivers have such fix ?

**Stephen Warren** · 05-27-09, 10:40 PM

Yes, it's the "VDPAU/PowerMizer interaction" entry in the changelog.

jyavenard · 05-28-09, 12:40 AM

Excellent. I will try it.

I may build my mythtv packages against 185 drivers from now on...

Jean-Yves

05-27-09, 03:30 AM	#1
jyavenard MythTV developer Join Date: Mar 2006 Posts: 413	Problem with 9800GT and VDPAU Hi Trying to help someone getting his 9800GT to work with VDPAU. And I haven't had much luck.. I've identified the issue to be related to the speed the card is running at. GPU is at 300Mhz by default and Video RAM is at 100MHz In the default mode, H264 720p video decoding is very sketchy in MythTV, 1080i is even worse. Running glxinfo at the same time, change the speed to 600MHz / 900MHz and at that speed, playback with VDPAU is fine... Now, the problem is that as soon as I stop glxinfo, the clock goes back to 300 / 100Mhz... Video drivers is 180.60. Any ideas on a work around ? Thank you Jean-Yves

05-27-09, 04:07 AM	#2
thefirstm Registered User Join Date: Feb 2009 Posts: 226	Re: Problem with 9800GT and VDPAU There was another thread about this a while back. The devs said they were looking into a fix, but I haven't read anything else. I do have a recommendation, though. If possible, try disabling Composite by adding this: Section "Extensions" Option "Composite" "disable" EndSection to the xorg .conf. This is a dirty workaround, but evidently the overlay output method (used when Composite is off) is much less GPU-intensive than the Blit output method (used when it is on.) This workaround does not affect the clock-speed of the GPU, but it does enable my 8600m GT to decode SD MPEG2 or H264 video smoothly. I will test HD in a minute.

05-27-09, 04:18 AM	#3
jyavenard MythTV developer Join Date: Mar 2006 Posts: 413	Re: Problem with 9800GT and VDPAU Disabling Composite has nothing to do with my problem. First, composite is already disabled and second, disabling composite is only required to prevent tearing. The issue I'm reporting here is that the nvidia GPU is set at a too low frequency and running VDPAU doesn't raise the clock speed sufficiently. I've played with some settings like: Option "RegistryDwords" "PowerMizerLevelAC=0x1" in the device section, it does start playing properly.. But after a few minutes, video playback becomes choppy again... The speed of the video card becomes 600 (GPU) / 900Mhz (RAM) with the 0x1 settings

05-27-09, 04:33 AM	#4
thefirstm Registered User Join Date: Feb 2009 Posts: 226	Re: Problem with 9800GT and VDPAU Have you tried the latest beta driver version? This might help the issue as well.

05-27-09, 05:25 AM	#5
jyavenard MythTV developer Join Date: Mar 2006 Posts: 413	Re: Problem with 9800GT and VDPAU I just tried with the latest beta 185.18.10 It is a tad better, but after about 2 minutes , it becomes all jerky again ...

05-27-09, 11:08 AM	#6
Stephen Warren Moderator Join Date: Aug 2005 Posts: 1,327	Re: Problem with 9800GT and VDPAU This is probably a known issue with PowerMizer. We believe we've fixed it, and should be in a driver fairly soon.

05-27-09, 09:21 PM	#7
jyavenard MythTV developer Join Date: Mar 2006 Posts: 413	Re: Problem with 9800GT and VDPAU Does the new 185.18.14 RC drivers have such fix ?

05-27-09, 10:40 PM	#8
Stephen Warren Moderator Join Date: Aug 2005 Posts: 1,327	Re: Problem with 9800GT and VDPAU Yes, it's the "VDPAU/PowerMizer interaction" entry in the changelog.

05-28-09, 12:40 AM	#9
jyavenard MythTV developer Join Date: Mar 2006 Posts: 413	Re: Problem with 9800GT and VDPAU Excellent. I will try it. I may build my mythtv packages against 185 drivers from now on... Jean-Yves