Incorrect frequencies returned by xrandr

torturedutopian · 10-23-07, 01:30 PM

Hi everyone !

Here's an issue I've been experiencing for about one year, with different linux versions, and two different gfx boards : 6600 and 8600 GTS.

I generated my xorg.conf with nvidia-settings. So the right frequencies are supposed to be obtained through EDID. (this is a LG L1915S LCD screen)

Indeed, in nvidia-settings, I see 60 Hz and 75 Hz as available frequencies. My monitor OSD confirms those frequencies.

However, other pieces of software seem to be confused.

Example, when I type "xrandr" I get the following frequencies :

Code:

1280x1024      50.0     51.0

I see those very same frequencies in the Gnome resolution selector as well.

I figured out that when choosing 50 Hz, it actually set 60 Hz, and when choosing 51 Hz, the actual frequency was 75 Hz.

See : http://mahen.free.fr/images/frequencies.jpg

Why am I complaining ?

Actually because I'm afraid it may have some other unexpected consequences. Example : in compiz, the option to detect the refresh frequency automatically give me a little choppy experience.

What do you people think about this ?

Thanks a lot for reading & best regards !

netllama · 10-23-07, 01:32 PM

This is expected behavior. See the driver README's discussion of DynamicTwinview.

torturedutopian · 10-23-07, 01:36 PM

Thanks for the incredibly fast reply, I guess I didn't spend enough time investigating, sorry :-/

cheers

torturedutopian · 10-23-07, 02:07 PM

Appending the "Option "DynamicTwinView" "false"" to my xorg / device section, I now get a muuuch smoother experience.

Example, in the game "Ankh", which was a little choppy before (w/ compiz enabled, at least). And it seems also better with Compiz, this time I get keep the "detect framerate" ticked.

Hurray, thanks a lot

10-23-07, 01:30 PM	#1
torturedutopian Registered User Join Date: Oct 2007 Posts: 28	Incorrect frequencies returned by xrandr Hi everyone ! Here's an issue I've been experiencing for about one year, with different linux versions, and two different gfx boards : 6600 and 8600 GTS. I generated my xorg.conf with nvidia-settings. So the right frequencies are supposed to be obtained through EDID. (this is a LG L1915S LCD screen) Indeed, in nvidia-settings, I see 60 Hz and 75 Hz as available frequencies. My monitor OSD confirms those frequencies. However, other pieces of software seem to be confused. Example, when I type "xrandr" I get the following frequencies : Code: 1280x1024 50.0 51.0 I see those very same frequencies in the Gnome resolution selector as well. I figured out that when choosing 50 Hz, it actually set 60 Hz, and when choosing 51 Hz, the actual frequency was 75 Hz. See : http://mahen.free.fr/images/frequencies.jpg Why am I complaining ? Actually because I'm afraid it may have some other unexpected consequences. Example : in compiz, the option to detect the refresh frequency automatically give me a little choppy experience. What do you people think about this ? Thanks a lot for reading & best regards !

10-23-07, 01:32 PM	#2
netllama NVIDIA Corporation Join Date: Dec 2004 Posts: 8,763	Re: Incorrect frequencies returned by xrandr This is expected behavior. See the driver README's discussion of DynamicTwinview.

10-23-07, 01:36 PM	#3
torturedutopian Registered User Join Date: Oct 2007 Posts: 28	Re: Incorrect frequencies returned by xrandr Thanks for the incredibly fast reply, I guess I didn't spend enough time investigating, sorry :-/ cheers

10-23-07, 02:07 PM	#4
torturedutopian Registered User Join Date: Oct 2007 Posts: 28	Re: Incorrect frequencies returned by xrandr Appending the "Option "DynamicTwinView" "false"" to my xorg / device section, I now get a muuuch smoother experience. Example, in the game "Ankh", which was a little choppy before (w/ compiz enabled, at least). And it seems also better with Compiz, this time I get keep the "detect framerate" ticked. Hurray, thanks a lot

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