Monitor resolution

bonixavier · 05-08-2011, 11:58 AM

Something that has been bugging me in my new netbook:

The graphics card is an Intel GMA3150 and the max resolution I get in Linux is 1024x600. On Windows 7, I could get higher resolutions - I guess one of them was 1024x780, but I can't say for sure because I wiped it off after I learned I couldn't even change the wallpaper. Can I change that switching to the Intel driver in /testing? Or should I set the resolution manually in a .conf file? If so, how can I do that?

Lirey · 05-08-2011, 01:18 PM

I don't have any systems currently running Linux with the Intel GMA3150 graphics, but I've installed Slackware(-current, between 13.1 and 13.37) on a number of Atom/NM10/GMA3150 systems. As far as I can recall, I had no problems getting 1600x1200 resolution. I did not need to use the driver in /testing, just the default driver that was installed.

(Off topic, Slackware recognized all the hardware in these systems without any additional drivers and ran flawlessly. When I installed Windows 7 on the same hardware, Windows failed to recognize the video, sound, and network until third party drivers were installed for each.)

I suspect that X11 is not properly recognizing the capabilities of your monitor. Have you tried running 'xorgsetup'? This should create an X11 configuration file: /etc/X11/xorg.conf If you've run xorgsetup and still are not seeing the resolutions that you want as an option, you can try manually editing the file.

Look in the configuration file for a section called "Screen" and a subsection called "Display". There should be a line that lists the modes that the monitor can display. By default it looks like:

Modes "1024x768" "800x600" "640x480"

You can edit this line to add any other resolutions that your monitor can handle. For instance, the line in my xorg.conf looks like:

Modes "1920x1200" "1600x1200" "1280x1024" "1024x768" "800x600" "640x480"

Once the configuration file has been updated, you should have these resolutions available the next time you start the GUI. I think KDE will automatically start in whatever resolution it was using last, but the option to switch to the new resolutions should be available in the KDE system settings.

Lirey

bonixavier · 05-08-2011, 03:14 PM

Thank you Lirey for you repply. Based on your suggestion, I ran xorgsetup and added the modes line to the display subsection. I added a line like this to all the display subsections:

Code:

Modes "1152x864" "1024x768" "1024x600" "800x600" "640x480"

But I still couldn't change the resolution to anything higher than 1024x600. I then ran xrandr and got this output:

Code:

Screen 0: minimum 320 x 200, current 1024 x 600, maximum 4096 x 4096
LVDS1 connected 1024x600+0+0 (normal left inverted right x axis y axis) 223mm x 125mm
   1024x600     60.2*+
   800x600      60.3     56.2
   640x480      59.9
VGA1 disconnected (normal left inverted right x axis y axis)

Based on what it said in maximum, I tried to set it to 1152x864:

Code:

xrandr --output LVDS1 --mode 1152x864

and got

Code:

xrandr: cannot find mode 1152x864

What can I do to make xorg aware of those modes?

adamk75 · 05-08-2011, 03:27 PM

You can created a modeline with cvt or gtf and add it to the Monitor section of your xorg.conf file.

Adam

bonixavier · 05-08-2011, 03:37 PM

Quote:

Originally Posted by adamk75

You can created a modeline with cvt or gtf and add it to the Monitor section of your xorg.conf file.

Adam

Hi. I tried both methods, but none of them got assigned to LVDS1, but to VGA1. What am I doing wrong? I did this:

Code:

gtf 1152  864 60.4
xrandr --newmode "1152x768" 82.17 1152 1216 1336 1520 864 865 868 895 -Hsync +Vsync

adamk75 · 05-08-2011, 04:22 PM

Then use xrandr with --addmode to add it to a particular output device. You can add the modeline to a monitor section, but the Identifier for the monitor section will need to be the output device name given by xrandr.

Adam

bonixavier · 05-08-2011, 04:37 PM

I'll paste everything that I'm doing and also the output I get from the computer.

:~# xrandr

Code:

Screen 0: minimum 320 x 200, current 1024 x 600, maximum 4096 x 4096
LVDS1 connected 1024x600+0+0 (normal left inverted right x axis y axis) 223mm x 125mm
   1024x600     60.2*+
   800x600      60.3     56.2
   640x480      59.9
VGA1 disconnected (normal left inverted right x axis y axis)

:~# gtf 1152 864 60.2

Code:

  # 1152x864 @ 60.20 Hz (GTF) hsync: 53.88 kHz; pclk: 81.90 MHz
  Modeline "1152x864_60.20"  81.90  1152 1216 1336 1520  864 865 868 895  -HSync +Vsync

:~# xrandr --newmode "1152x864_60.20" 81.90 1152 1216 1336 1520 864 865 868 895 -HSync +Vsync

:~# xrandr --addmode LVDS1 1152x864_60.20

Code:

X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  149 (RANDR)
  Minor opcode of failed request:  18 (RRAddOutputMode)
  Serial number of failed request:  25
  Current serial number in output stream:  26

:~# xrandr --output LVDS1 --mode 1152x864_60.20

Code:

xrandr: cannot find mode 1152x864_60.20

I really don't know where my mistake is.

adamk75 · 05-08-2011, 05:16 PM

I really don't know if it matters in this situation, but you really shouldn't be running these commands as root. Does --addmode work if you put the mode name in quotes:

Code:

xrandr --addmode LVDS1 "1152x864_60.20"

bonixavier · 05-08-2011, 05:22 PM

No. Same error message. This is frustrating.

adamk75 · 05-08-2011, 05:35 PM

Sorry, no idea then. I've done that plenty of times with the radeon driver but not with intel.

bonixavier · 05-08-2011, 05:41 PM

Quote:

Originally Posted by adamk75

Sorry, no idea then. I've done that plenty of times with the radeon driver but not with intel.

Thank you for helping me. Turns out that the higher resolution it can get in Windows is actually not native and is not achievable in Linux. I found this online:

Quote:

At last night's meeting, I mentioned that my Samsung N150 was capable of 1024 x 768 resolution in Windows 7 Starter Edition, but would only give me 1024 x 600 resolution in Ubuntu, and I was trying to figure out how to get the higher resolution in Ubuntu. Unfortunately, I learned today that the supposed 1024 x 768 mode in Windows is achieved by having the driver discard 168 scan lines of info, presumably spaced out across the screen, so the real resolution is only 1024 x 600. I have run into a couple of programs on Ubuntu, notably the Pan Usenet program, that open dialog boxes that are a full 768 pixels high, and have command buttons off-screen when used on a 1024 x 600 display.

That sucks because XFCE's terminal settings dialog doesn't fit my screen, for example. >-( Suppose I should have gotten another model.

bonixavier · 05-08-2011, 05:46 PM

But why the heck does xrandr report 4096x4096 as the max resolution? Is it the one the video card is capable of, but the monitor isn't?

adamk75 · 05-08-2011, 05:50 PM

It's telling you that the driver allocated enough video RAM to support that high of a resolution across all possible output devices.

Adam

Lirey · 05-08-2011, 06:53 PM

I'm not very familiar with xrandr, but if it is reporting 4096x4096 as the maximum resolution it must be reporting the capabilities of the video card/video hardware, not the monitor/display itself. In a nettop type system with an external monitor, the GMA3150 graphics can handle a relatively high resolution - although 4096x4096 seems a bit absurd for integrated graphics.

Do you know what is the hardware resolution of your display? The Samsung N150 mentioned above seems to have some conflicting specifications, but most indicate that it has a 1024x600 (WSVGA) display.

Does XFCE allow a virtual desktop that is larger than the display resolution? I'm not sure if current versions of the desktop environments still support this feature, but it used to be quite useful when configuring systems connected to small (12 or 13 inch CRT with VGA max resolution) displays.

igordcard · 01-15-2012, 09:03 AM

So, the question is: Is there a known way to force a resolution by discarding some exceeding lines along the way, in Linux? Also, my netbook can do 1152x864 in Windows (the panel is 1024x600 native, the max resolution in GNU/Linux). In this case, not only additional height is being added, but width too.