How do I use kscreen?

Duncan 1i5t5.duncan at
Thu Nov 6 08:42:30 GMT 2014

Nikos Chantziaras posted on Wed, 05 Nov 2014 14:27:14 +0200 as excerpted:

> On 05/11/14 09:51, Duncan wrote:
>> BTW, @ Nikos, I just discovered the "kscreen-console" command
> Everything seems fine. The NVidia driver supports xrandr 1.4 and I had
> zero problems configuring everything with krandr. It really seems the
> GUI is just not implemented correctly.
> This is the output:

>From that pastebin...

Mode:  "644" 
Preferred Mode:  "643" 
Preferred modes:  ("643") 
         "643"    "1024x768"   QSize(1024, 768)   84.9967 
         "668"    "640x480"   QSize(640, 480)   85.0083 
         "644"    "1920x1080"   QSize(1920, 1080)   60 

Something's setting the "preferred" mode to #643, 1024x768 @ 85Hz 
refresh, altho here you've apparently manually set (presumably using the 
nVidia tool you mentioned) #644, 1920x1080 @ 60Hz.

Normally that "something" would be the full EDID info from the monitor 
itself.  I'm not sure whether the nVidia xorg driver does this tho I hope 
so, but the radeon driver has I believe since the xfree86 era always 
displayed rather detailed (I believe fully expanded) EDID data from each 
monitor on xorg initialization, in /var/log/Xorg.0.log (and before that 
the xfree86 version of same).

Assuming you have that output in the xorg log, does it show the same 
"preferred" resolution?  Assuming native resolution is 1920x1080, that 
would seem to be a defective monitor EDID if so.  Here's what my radeon 
output looks like...

[   249.259] (II) RADEON(0): EDID for output HDMI-0
[   249.259] (II) RADEON(0): EDID Version: 1.3
[   249.259] (II) RADEON(0): First detailed timing is preferred mode
[   249.260] (II) RADEON(0): Supported established timings:
[   249.260] (II) RADEON(0): 720x400 at 70Hz
[   249.260] (II) RADEON(0): Supported standard timings:
[   249.260] (II) RADEON(0): #0: hsize: 640  vsize 480  refresh: 60  vid: 
[   249.260] (II) RADEON(0): Supported detailed timing:
[   249.260] (II) RADEON(0): clock: 148.5 MHz   Image Size:  1600 x 900 mm
[   249.260] (II) RADEON(0): h_active: 1920  h_sync: 2008  h_sync_end 
2052 h_blank_end 2200 h_border: 0
[   249.260] (II) RADEON(0): v_active: 1080  v_sync: 1084  v_sync_end 
1089 v_blanking: 1125 v_border: 0
[   249.260] (II) RADEON(0): Supported detailed timing:
[   249.260] (II) RADEON(0): clock: 85.5 MHz   Image Size:  1600 x 900 mm
[   249.260] (II) RADEON(0): h_active: 1360  h_sync: 1424  h_sync_end 
1536 h_blank_end 1792 h_border: 0
[   249.260] (II) RADEON(0): v_active: 768  v_sync: 771  v_sync_end 777 
v_blanking: 795 v_border: 0
[   249.260] (II) RADEON(0): Ranges: V min: 58 V max: 62 Hz, H min: 30 H 
max: 83 kHz, PixClock max 165 MHz
[   249.260] (II) RADEON(0): Monitor name: LG TV
[more detail timings, followed by the raw EDID in Hex]

Then further down (after the other ports are taken care of)...

[   249.321] (II) RADEON(0): Output HDMI-0 using initial mode 1920x1080

Note that it says first *DETAILED* timing is preferred.  The established 
and standard timings are compatibility/legacy timings.  It's the first 
DETAILED timing that's preferred, and as you can see here, that's 
1920x1080 (the h_active and v_active numbers) for this LG TV.  The dot-
clock (aka PixClock) for that timing is 148.5 MHz.

If your xorg log EDID has a preferred (likely first DETAILED) timing/
resolution of 1024x768 and you're definitely using a native 1920x1080 
full-HD monitor, then very likely that monitor EDID is defective and 
reporting the wrong thing.

If OTOH, the EDID in xorg is saying 1920x1080 is preferred, then it's 
gotta be the drivers screwing things up, tho at this point I'm pretty 
sure it's going to be the monitor and the driver is simply a reporter of 
the facts as it collects them, caught in the crossfire.

Either way, kscreen/xrandr/krandr is getting preferred 1024x768, one can 
hardly fault it for going with that, in the absence of an xorg.conf 
setting overriding that with something else, which is what I'd do in that 

Also of interest is the ranges line, 58-62 Hz vertical refresh, 30-83 kHz 
horizontal line frequency, 165 MHz max dotclock/pixclock, which can be 
fed into various modeline generators to generate custom resolution 
modelines, as I mentioned before.  Here's a google:

Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman

This message is from the kde mailing list.
Account management:
More info:

More information about the kde mailing list