Samsung NP305V5A: Dual-screen does not work

mityukov · 2013-12-11 11:09:57

I can switch to the "Big" display and back to Notebook's one, but I can't make them work both at the same time.

I've tried KScreen, then command-line xrandr. The best I could achieve was that one of monitors is ON, there is a kind of "pit" highlighted(by KWin) at the position, where the area, controlled by another monitor should be and the mouse cursor can be driven into that area (blindly), but the second monitor is black.

Note: I've just been able to blindly "catch" a window on that another imaginary screen (by <Alt> + "Click") and drag it to the visible screen. So, the "system"is pretty sure that I have something "there".

Any advises on how to fix or troubleshoot this issue?

By the way: when playing around, I sometimes get desktop with different background, plasmoids(there are no any) and windows opened. It's not another virtual desktop (cause my virtual desktops all have the same bg&plasmoids), and this is not another Activity.. What it it then? And how to switch between this "another" and my primary desktop?

$ lspci | grep VGA
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] BeaverCreek [Radeon HD 6520G]
02:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Seymour [Radeon HD 6400M/7400M Series]

Video driver: radeon

Kernel parameters: root=/dev/sda2 rw radeon.dpm=1
(note: radeon.dpm=1 helps a lot; before kernel v3.11 I could not use radeon at all)

/etc/X11/xorg.conf.d/20-radeon.conf

Section "Device"
    Identifier  "Radeon"
    Driver      "radeon"
    Option      "ZaphodHeads"   "VGA-0"
    Option      "ColorTiling2D" "false"
EndSection

xrandr output for my current state (with that "imaginary" screen, described at the top):

Screen 0: minimum 320 x 200, current 1920 x 1848, maximum 8192 x 8192
VGA-0 connected 1920x1080+0+768 (normal left inverted right x axis y axis) 477mm x 268mm
   1920x1080      60.0*+
   1600x1200      60.0  
   1680x1050      60.0  
   1280x1024      75.0     60.0  
   1440x900       75.0     59.9  
   1280x960       60.0  
   1280x800       59.8  
   1152x864       75.0  
   1024x768       75.1     70.1     60.0  
   832x624        74.6  
   800x600        72.2     75.0     60.3     56.2  
   640x480        75.0     72.8     66.7     60.0  
   720x400        70.1  
LVDS connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1366x768       60.0*+
   1280x720       59.9  
   1152x768       59.8  
   1024x768       59.9  
   800x600        59.9  
   848x480        59.7  
   720x480        59.7  
   640x480        59.4  
HDMI-0 disconnected (normal left inverted right x axis y axis)

mityukov · 2013-12-11 11:15:42

Another notice: when I switch to the big screen, the notebook's screen turns OFF (completely). But when I'm trying to enter dual-screen mode -- the notebook's screen seems to be "partly ON" (it looks like it has backlight ON, but only displays black color).

montefuscolo · 2013-12-17 13:11:43

What happens if you try:

xrandr --output VGA-0 --mode 1920x1080  --above LVDS --output LVDS --mode 1366x768 --primary

Ps: Some time ago I had a strange problem with my dual head. The max resolution was 1024x768 for external screen and I tried all configurations possible. A new HDMI cable solved the problem!!!

satanselbow · 2013-12-17 13:25:07

montefuscolo wrote:

What happens if you try:

xrandr --output VGA-0 --mode 1920x1080  --above LVDS --output LVDS --mode 1366x768 --primary

Had this on a keybind since... well for a very long time... Specifying modes is a pain if you are connecting to different displays for differing purposes (TV for movies/gaming, Spare monitor for coding etc) and should offer the highest detected resolution possible on the 2ndary display by default.

xrandr --output LVDS --auto  --output HDMI --auto --above LVDS1

check

xrandr --help

for a com'prehensive list of possibilities... you can of course add as many displays as you have ports using the same format.

To turn off the external display when you have finished with it just do

xrandr HDMI --off

Again can be attached to a keybind

*** I've used HDMI as an example but the pattern remains the same once you know what xrandr has to offer ***

Last edited by satanselbow (2013-12-17 13:27:26)

Jojonintendo · 2013-12-17 14:04:52

I think I have the same laptop (not absolutely sure, I don't have it right now), with AMD A8 processor and dual graphics, right?

I recently tried multiscreen with a 47' TV, and it works like a charm. I can use both screens like a big one (like you describe above) or the two as different desktops, the TV works at 1920x1080p. I use latest GNOME, kernel, radeon and mesa.

mityukov · 2014-03-12 12:48:26

montefuscolo wrote:

What happens if you try:

xrandr --output VGA-0 --mode 1920x1080  --above LVDS --output LVDS --mode 1366x768 --primary

It works! It works!

I really don't know what I've done differently myself... But this works like a charm.

How about making this happen automatically just when I plug big monitor in?

Arch Linux

#1 2013-12-11 11:09:57

Samsung NP305V5A: Dual-screen does not work

#2 2013-12-11 11:15:42

Re: Samsung NP305V5A: Dual-screen does not work

#3 2013-12-17 13:11:43

Re: Samsung NP305V5A: Dual-screen does not work

#4 2013-12-17 13:25:07

Re: Samsung NP305V5A: Dual-screen does not work

#5 2013-12-17 14:04:52

Re: Samsung NP305V5A: Dual-screen does not work

#6 2014-03-12 12:48:26

Re: Samsung NP305V5A: Dual-screen does not work

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