How to disable dithering on NV Qaudro FX

johncom · 02-24-11, 07:53 AM

Conf.:
X.Org server 1.6.5
SLED 11 SP 1 ker. 2.6.32.12
NVdriver 260.19.36

Problem:
very bad performance out of "PCoIP - KVM extension" when using NV Qaudro FX 380/580 cards. The cards are OK when connected directly without PCoIP part.

The problem seems to be related to dithering - frequent unnecessary screen updates.
How can I permanently disable dithering?
How to check the state of dithering?
I have tried following with no success:
1.
nvidia-setting utility:
GPU-0 - DFP-0 - Dithering Controls - Dithering Auto (switch to disabled)
it keeps on being auto - How to save disabled option?
2.
configuration of xorg.conf
Section “Screen”
Identifier ...
Device ...
…
Option "Dac8Bit" "False"
Option "RegistryDwords" "DitherAlgo8=3; DitherAlgo6=3"
It does not work for me.

regards V.

**AaronP** · 02-24-11, 09:20 AM

Try

Option "FlatPanelProperties" "Dithering=Disabled"

or

Option "FlatPanelProperties" "DitheringMode=Static-2x2"

**danix** · 02-24-11, 07:41 PM

The nvidia-settings control panel in recent 270 releases also has an option to disable this (in the settings panel for each display).

[edit: sorry; the 260 control panel has this too, as noted by johncom, but the setting isn't persistent unless added to the X config.]

johncom · 02-25-11, 09:02 AM

Both Options do the job. Thank you for prompt answer.
Reagards V.

02-24-11, 07:53 AM	#1
johncom Registered User Join Date: Apr 2010 Posts: 7	How to disable dithering on NV Qaudro FX Conf.: X.Org server 1.6.5 SLED 11 SP 1 ker. 2.6.32.12 NVdriver 260.19.36 Problem: very bad performance out of "PCoIP - KVM extension" when using NV Qaudro FX 380/580 cards. The cards are OK when connected directly without PCoIP part. The problem seems to be related to dithering - frequent unnecessary screen updates. How can I permanently disable dithering? How to check the state of dithering? I have tried following with no success: 1. nvidia-setting utility: GPU-0 - DFP-0 - Dithering Controls - Dithering Auto (switch to disabled) it keeps on being auto - How to save disabled option? 2. configuration of xorg.conf Section “Screen” Identifier ... Device ... … Option "Dac8Bit" "False" Option "RegistryDwords" "DitherAlgo8=3; DitherAlgo6=3" It does not work for me. regards V.

02-24-11, 09:20 AM	#2
AaronP NVIDIA Corporation Join Date: Mar 2005 Posts: 2,487	Re: How to disable dithering on NV Qaudro FX Try Option "FlatPanelProperties" "Dithering=Disabled" or Option "FlatPanelProperties" "DitheringMode=Static-2x2"

02-24-11, 07:41 PM	#3
danix NVIDIA Corporation Join Date: Feb 2010 Location: Santa Clara, CA Posts: 237	Re: How to disable dithering on NV Qaudro FX The nvidia-settings control panel in recent 270 releases also has an option to disable this (in the settings panel for each display). [edit: sorry; the 260 control panel has this too, as noted by johncom, but the setting isn't persistent unless added to the X config.]

02-25-11, 09:02 AM	#4
johncom Registered User Join Date: Apr 2010 Posts: 7	Re: How to disable dithering on NV Qaudro FX Both Options do the job. Thank you for prompt answer. Reagards V.