incorrect max. screen resolution due to invalid EDID data

[lockheed02]

I thought I'd share as it might be useful to others as well. After successfully installing nvidia binary driver I was only offered 1024x768 screen resoultion but my screen can do 1280x1024.

My Xorg.0.log file showed lines like that

[  9792.343] (WW) NVIDIA(GPU-0): The EDID read for display device CRT-0 is invalid:
[  9792.343] (WW) NVIDIA(GPU-0):     unrecognized EDID Header.

Neitther read-edid nor monitor-get-edid programs could help me. So I disabled automatic EDID usage and added a modeline manually (using the "# gtf 1280 1024 60" command) in xorg.conf file,

[root@beefy ~]# gtf 1280 1024 60

  # 1280x1024 @ 60.00 Hz (GTF) hsync: 63.60 kHz; pclk: 108.88 MHz
  Modeline "1280x1024_60.00"  108.88  1280 1360 1496 1712  1024 1025 1028 1060  -HSync +Vsync

but still something didn't work out as the Xorg.0.log still showed:

[  9792.463] (II) NVIDIA(0): Assigned Display Device: CRT-0
[  9792.463] (WW) NVIDIA(0): No valid modes for "1280x1024_60x00"; removing.
[  9792.463] (WW) NVIDIA(0): 
[  9792.463] (WW) NVIDIA(0): Unable to validate any modes; falling back to the default mode
[  9792.463] (WW) NVIDIA(0):     "nvidia-auto-select".
[  9792.463] (WW) NVIDIA(0): 
[  9792.463] (II) NVIDIA(0): Validated modes:
[  9792.463] (II) NVIDIA(0): Virtual screen size determined to be 1024 x 768

So I enabled debug output and default configuration.

# nvidia-xconfig --no-use-edid
# nvidia-xconfig --mode-debug

(alternatively add Option "ModeDebug" "True" into Screen section)


Now I got the real cause of the information why my line got rejected:

[  8713.031] (--) NVIDIA(0): No EDID Available.
[  8713.031] (--) NVIDIA(0): 
[  8713.031] (--) NVIDIA(0): --- End of EDID for CRT-0 ---
[  8713.031] (--) NVIDIA(0): 
[  8713.127] (**) NVIDIA(0): Using HorizSync/VertRefresh ranges from the EDID for display
[  8713.127] (**) NVIDIA(0):     device CRT-0 (Using EDID frequencies has been enabled on
[  8713.127] (**) NVIDIA(0):     all display devices.)
[  8713.127] (II) NVIDIA(0): Frequency information for CRT-0:
[  8713.127] (II) NVIDIA(0):   HorizSync   : 28.000-55.000 kHz
[  8713.127] (II) NVIDIA(0):   VertRefresh : 43.000-72.000 Hz
[  8713.127] (II) NVIDIA(0):     (HorizSync from Conservative Defaults)
[  8713.127] (II) NVIDIA(0):     (VertRefresh from Conservative Defaults)
[  8713.127] (II) NVIDIA(0): 
[  8713.127] (II) NVIDIA(0): --- Building ModePool for CRT-0 ---
[  8713.127] (II) NVIDIA(0):   Validating Mode "1280x1024_60.00":
[  8713.127] (II) NVIDIA(0):     1280 x 1024 @ 60 Hz
[  8713.127] (II) NVIDIA(0):     Mode Source: X Configuration file ModeLine
[  8713.127] (II) NVIDIA(0):       Pixel Clock      : 108.88 MHz
[  8713.127] (II) NVIDIA(0):       HRes, HSyncStart : 1280, 1360
[  8713.127] (II) NVIDIA(0):       HSyncEnd, HTotal : 1496, 1712
[  8713.127] (II) NVIDIA(0):       VRes, VSyncStart : 1024, 1025
[  8713.127] (II) NVIDIA(0):       VSyncEnd, VTotal : 1028, 1060
[  8713.127] (II) NVIDIA(0):       H/V Polarity     : -/+
[  8713.127] (WW) NVIDIA(0):     Mode is rejected: HorizSync (63.6 kHz) out of range
[  8713.127] (WW) NVIDIA(0):     (28.000-55.000 kHz).

According to that my used HorizSync value was simply outside range of the "conservative" range.

So now simply adjusting that HorizSync value in Monitor section of xorg.conf:

Section "Monitor"
  # 1280x1024 @ 60.00 Hz (GTF) hsync: 63.60 kHz; pclk: 108.88 MHz
    Identifier     "CRT-0"
    VendorName     "Samsung"
    ModelName      "VisionMagic"
    HorizSync       28.0 - 63.7
    ModeLine       "1280x1024_60.00" 108.88 1280 1360 1496 1712 1024 1025 1028 1060 -hsync +vsync
EndSection
...

And now suddenly nvidia-settings and also "System Settings" offer that 1280x1024 resolution. Xorg.0.log says now:

[    22.320] (II) NVIDIA(0):   Validating Mode "1280x1024":
[    22.320] (II) NVIDIA(0):     1280 x 1024 @ 60 Hz
[    22.320] (II) NVIDIA(0):     Mode Source: X Server
[    22.320] (II) NVIDIA(0):       Pixel Clock      : 108.00 MHz
[    22.320] (II) NVIDIA(0):       HRes, HSyncStart : 1280, 1328
[    22.320] (II) NVIDIA(0):       HSyncEnd, HTotal : 1440, 1688
[    22.320] (II) NVIDIA(0):       VRes, VSyncStart : 1024, 1025
[    22.320] (II) NVIDIA(0):       VSyncEnd, VTotal : 1028, 1066
[    22.320] (II) NVIDIA(0):       H/V Polarity     : +/+
[    22.320] (II) NVIDIA(GPU-0):     BestFit Centered         1280x1024
[    22.320] (II) NVIDIA(GPU-0):       Horizontal Taps        0
[    22.320] (II) NVIDIA(GPU-0):       Vertical Taps          0
[    22.321] (II) NVIDIA(GPU-0):       Base SuperSample       x4
[    22.321] (II) NVIDIA(GPU-0):       Base Depth             32
[    22.321] (II) NVIDIA(GPU-0):       Distributed Rendering  1
[    22.321] (II) NVIDIA(GPU-0):       Overlay Depth          32
[    22.321] (II) NVIDIA(0):     Mode is valid.

I hope this gives some hints in case you come across similar issues.

Lockheed

[jkfjlkasdjfkljk]

Joined this forum just to say thank you for this post.

[lockheed02]

You're welcome. Although I thought I'm the only one who has such an issue.

Lockheed