vertical refresh rates

[ehe123]

I do not understand how the vertical refresh rates are being set. I am using RedHat 8, with a Quadro4 700 XGL and a Viewsonic P225F monitor. I purchased this monitor because it supports high refresh rates (30-127 kHZ H, and 50-180 Hz V) that I want to use for page-flipping stereo.
1) When I use the graphical utility for setting the screen display parameters, the only options are screen resolution, and then monitor parameters. I assume that the vertical refresh rate is computed automatically.
2) But when I am in 1600 x 1200, the vertical refresh is listed as 85 Hz (using xvidtune), and when I switch to 1280 x 1024, the refresh is still 85 Hz. If the vertical refresh is chosen as the maximum possible, why is it not increased when I go to the lower resolution?
3) Is there a problem that in the attached XF86Config the card is listed as a GeForce 4?

[Wolfman [TWP]]

What are your refresh rate settings in your XF86Config(-4) file?? (I personally still don't quite understand how Linux does this, but from what I've read, the settings in that file will goven the refresh rates for the given resolutions. Unless there's a manual way of doing it that I don't know of.)

Wolf

[ehe123]

I had attached the XF86Config file to my post in the hopes that this would be useful. The relevant section, which does not show how the vertical refresh gets established, is:
Section "Screen"
Identifier "Screen0"
Device "NVIDIA GeForce 4 (generic)"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Depth 16
Modes "1600x1200" "1400x1050" "1280x1024" "1280x960" "1152x864" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1600x1200" "1400x1050" "1280x1024" "1280x960" "1152x864" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1600x1200" "1400x1050" "1280x1024" "1280x960" "1152x864" "1024x768" "800x600" "640x480"
EndSubSection
EndSection

[ehe123]

It appears that the file, XF86Config.txt, was never attached, so I am trying again!

[ehe123]

It appears that the problem may be the failure to return the EDID parameters from the board-monitor. At least, that is my interpretation of the log file attached. But there is no modeline in XF86Config. Does anyone know where this modeline is being written? I assume that I can manually change it, allowing a higher pixel clock rate (currently set at 229 MHz), with a high vertical refresh.

[Andy Mecham]

Your best bet is probably to construct a modeline that gives you the refresh values you're after. gtf is a program that shipped with XFree 4.3 (and should be pretty easy to find) that will create a modeline for you based on your input.

--andy

[ehe123]

I assumed that I would need to do this manually, since it appears that my Viewsonic monitor does not support DDC. Being a relative novice at Linux, I am not sure where this modeline would go! There is no file named Xconfig on my system, and I have not yet found any file which has "modename" in it.

[Andy Mecham]

/etc/X11/XF86Config - might be XF86Config-4.

--andy

[ehe123]

That is the problem! If you look at the attached file above, /etc/X11/XF86Config, there are no modelines in it. There are only "modes", which are then expanded somewhere else into modelines that appear in the log file. Here is a section from XF86Config:

SubSection "Display"
Depth 24
Modes "1600x1200" "1400x1050" "1280x1024" "1280x960" "1152x864" "1024x768" "800x600" "640x480"

Given this, can I enter a modeline in XF86Config? How will it be added to the existing modes that appear in the log file?
Thanks!

[ehe123]

I should have attached the log file earlier, since that might have helped. I have done that now (/var/log/Xfree86.0.log). You can see that GetModeLine is extracting modeline information, but from where? Is this just from default parameters, given that it cannot get EDID info. from my monitor?

[bwkaz]

XFree86 has an internal list of modelines (the number of them is dependent on the version of X you have, and the number of VESA-defined modes available on most cards when that version of X was released) that it uses.

You can add more modelines if needed by putting the ModeLine that gtf prints out, into the Monitor section in your config file.