Backlight gets reseted with VDPAU

[Stephen Warren]

How many people have tried:

Option "RegistryDwords" "EnableBrightnessControl=1"

I'm not sure which driver version introduce that; best to try the latest driver (260.19.29) to be sure.

I notice that damdim has, but has everyone else tried that just in case it works for them?

[xificurk]

Originally Posted by Stephen Warren

How many people have tried:

Option "RegistryDwords" "EnableBrightnessControl=1"

I have and I did not see any change, although I couldn't find any documentation regarding this option, so I've no idea what it is supposed to do.

Currently I'm using acpi/video in combination with nvidia_bl module to control the backlight, which is a partial success.
The need for nvidia_bl (or some similar module) was motivated by problems described in thread http://www.nvnews.net/vbulletin/showthread.php?t=156880
With nvidia_bl it seems to be mostly working, except the brightness resets described here in this thread and analyzed more in http://www.nvnews.net/vbulletin/show...&postcount=109 I got rid of most of the resets by changing KDE4 compositing backend to xrender instead of opengl and I don't use VDPAU, so the resets are now pretty rare for me, but the problem still exists.

[Zem]

Originally Posted by Stephen Warren

How many people have tried:

Option "RegistryDwords" "EnableBrightnessControl=1"

I have this too, with the nvidia driver included in ubuntu 10.04 (I can't remember the driver version) I had to use this option to make nvidia_bl work correctly.
In ubuntu 10.10 I didn't try without this option; as I wrote in the other thread (the one linked by guillaumezin) I have the problem described in this thread too.
I'm using the latest drivers.

[lonestar_italy]

I can confirm it's impossibile to change brightness on my Sony VPCCW1 (GT230m) without using nvidia_bl.

It's actually a long time issue, I've been owning this laptop for more than one year and the issue always existed with any version of Nvidia Linux drivers.

At the moment I've tested with 260.19.36 and EnableBrightnessControl=1 and it still won't work without nvidia_bl.

[Scoup]

I'm with the same problem using ubuntu 10.10 on vaio CW23FX. But only driver 256.53 works... 260+ I get only black screen. nvidia_bl is the only way to change the brightness.

[alessandro_ufms]

The brightness control still doesn't work here (nvidia 270.41.06 and geforce 330m). I have to use nvidia-bl to brightness works, but the problem with backlight gets reseted when a application use the video card acceleration (VDPAU, 3D programs, flashplayer, composite, etc.) continues. Any progress on this issue?

[damdim]

Originally Posted by alessandro_ufms

The brightness control still doesn't work here (nvidia 270.41.06 and geforce 330m). I have to use nvidia-bl to brightness works, but the problem with backlight gets reseted when a application use the video card acceleration (VDPAU, 3D programs, flashplayer, composite, etc.) continues. Any progress on this issue?

No progress so far. It's very annoying to have to adjust the backlight all the time...

[Zem]

So, still no news about this from nvidia developers?

[Zem]

If anybody is still affected by this (I was, and found it extremely annoying) it doesn't happen anymore on my system with the latest nvidia experimental drivers from ubuntu repositories (310.14).