How does Fedora determine supported resolutions?

[BadMofo666]

I'm using an HP 2009m 20" widescreen monitor, and have a Nvidia 8500gt video card. Latest Nvidia drivers from RPM Fusion are installed.

My problem is that the only widescreen resolution I have a choice of in both nvidia-settings and gnome's "Display preferences," is 1600x900. While this is fine for desktop apps, my video card doesn't handle games very well at that resolution.

So, I know my card and monitor are capable of displaying other widescreen resolutions (such as 1360x768) because they work in Windows 7, but Fedora doesn't give me the choice of selecting them.

Is there a file that Fedora uses to determine the supported resolutions? How would I be able to select resolutions that I know are supported (at least in Windows 7)? Can editing xorg.conf give me this ability?

I just looked in my xorg.conf, and it's surprisingly slim compared to others I've seen. Here it is if that would help:

# Xorg configuration created by livna-config-display

Section "Files"
	ModulePath   "/usr/lib64/xorg/modules/extensions/nvidia"
	ModulePath   "/usr/lib64/xorg/modules"
EndSection

Section "ServerFlags"
	Option	    "AIGLX" "on"
EndSection

Section "Device"
	Identifier  "Videocard0"
	Driver      "nvidia"
	Option	    "AddARGBGLXVisuals" "True"
EndSection

Section "Extensions"
	Option	    "Composite" "Enable"
EndSection

[Hlingler]

Xorg has a long history of using extremely narrow default ranges for HSync and VRefresh. Determine your monitor's true capabilities (based probably on MFR specs), and force in xorg.conf like so (required lines highlighted):

Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Unknown"
        ModelName    "COMPAQ FS7600"
        HorizSync    30.0 - 70.0
        VertRefresh  50.0 - 160.0
        Option      "DPMS"
EndSection

Section "Device"
        Identifier  "Videocard0"
        Driver      "nvidia"
        VendorName  "NVIDIA Corporation"
        BoardName   "GeForce 6150 LE"
        Option      "CustomEDID" "CRT-0:/etc/X11/edid.bin"
        Option      "TripleBuffer" "True"
        Option      "Coolbits" "1"
        Option      "MultisampleCompatibility" "true"
        Option      "UseEvents" "true"
        Option      "BackingStore" "true"
        Option      "OnDemandVBlankInterrupts" "true"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device     "Videocard0"
        Monitor    "Monitor0"
        DefaultDepth     24
        Option      "TwinView" "0"
        Option      "TwinViewXineramaInfoOrder" "CRT-0"
        Option      "metamodes" "1280x1024 +0+0"
        SubSection "Display"
                Depth     24
        EndSubSection
EndSection

Requires a re-start of X.

V

[newiLuvatar]

you can also use Nvidia Settings to see supported resolutions, change to them and save that to your xorg.conf...

[BadMofo666]

Originally Posted by Hlingler

Xorg has a long history of using extremely narrow default ranges for HSync and VRefresh. Determine your monitor's true capabilities (based probably on MFR specs), and force in xorg.conf like so (required lines highlighted):

Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Unknown"
        ModelName    "COMPAQ FS7600"
        HorizSync    30.0 - 70.0
        VertRefresh  50.0 - 160.0
        Option      "DPMS"
EndSection

Section "Device"
        Identifier  "Videocard0"
        Driver      "nvidia"
        VendorName  "NVIDIA Corporation"
        BoardName   "GeForce 6150 LE"
        Option      "CustomEDID" "CRT-0:/etc/X11/edid.bin"
        Option      "TripleBuffer" "True"
        Option      "Coolbits" "1"
        Option      "MultisampleCompatibility" "true"
        Option      "UseEvents" "true"
        Option      "BackingStore" "true"
        Option      "OnDemandVBlankInterrupts" "true"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device     "Videocard0"
        Monitor    "Monitor0"
        DefaultDepth     24
        Option      "TwinView" "0"
        Option      "TwinViewXineramaInfoOrder" "CRT-0"
        Option      "metamodes" "1280x1024 +0+0"
        SubSection "Display"
                Depth     24
        EndSubSection
EndSection

Requires a re-start of X.

V

Hmm, messed around with xorg.conf, but couldn't get it to use a resolution I wanted. Also couldn't find HorizSync, or VertRefresh range for my monitor so I used yours. I tried changing the "metamodes" option to a resolution that I wanted, but it would just start up with the same 1600x900 res. If I typed in a resolution that was on the list in gnome's display preferences, or nvidia-settings, then it would start X with that resolution, though. But that still doesn't help me get the resolutions not on the lists. is this possible?

Originally Posted by newiLuvatar

you can also use Nvidia Settings to see supported resolutions, change to them and save that to your xorg.conf...

That's the thing, Two resolutions that I want to use are not on the nvidia-settings list. But they do work on Windows 7, so I know that at least my hardware supports them. But I don't know how to get to them on Linux.

[Hlingler]

But they do work on Windows 7, so I know that at least my hardware supports them.

But that does not mean that the Linux version of the NVidia video driver supports them. Perhaps it simply does not.

You might try the custom EDID as I did. IIRC, I got a couple extra options out of it. Use the NVidia X-Config utility (or some other utility such as monitor-edid) to save the monitor's EDID, move it to folder /etc/X11/, and add the lines like I have shown to the xorg.conf (with correct monitor type, CRT or whatever). Requires a re-start of X11.

V

P.S. You did re-start X (or re-boot), correct?

[JEO]

Try adding some mode lines in the Monitor section:

ModeLine "1216x684_60" 66.05 1216 1248 1496 1528 684 698 705 719
ModeLine "1360x767_60" 84.37 1360 1392 1712 1744 767 782 790 806
ModeLine "1440x810_60" 95.28 1440 1472 1832 1864 810 826 834 851

[BadMofo666]

Originally Posted by JEO

Try adding some mode lines in the Monitor section:

ModeLine "1216x684_60" 66.05 1216 1248 1496 1528 684 698 705 719
ModeLine "1360x767_60" 84.37 1360 1392 1712 1744 767 782 790 806
ModeLine "1440x810_60" 95.28 1440 1472 1832 1864 810 826 834 851

Thank you. That worked. I used the Online Modeline Calculator, pasted the modeline into my Xorg file, and it worked perfectly.

[JEO]

The only odd thing about that modeline calculator is it puts an @ character in the name, which can be problematic so I changed it to an underscore.