Add new screen resolution in Linux Mint 
http://community.linuxmint.com/tutorial/view/877

 1. First step is to create modeline. This is done to get appropriate values of hsync, vsync and other parameters which are required to display a resolution properly in the backend. To add resolution of 1600x900, open terminal and type:

cvt 1280 768

This will create modeline for resolution of 1600x900 which will look something like this:

1280x768 59.87 Hz (CVT) hsync: 47.78 kHz; pclk: 79.50 MHz
Modeline "1280x768_60.00"   79.50  1280 1344 1472 1664  768 771 781 798 -hsync +vsync

These numbers may vary according to your monitor.
 

2. To add this resolution to monitor settings, type the following highlighted commands one by one:

xrandr --newmode "1280x768_60.00"   79.50  1280 1344 1472 1664  768 771 781 798 -hsync +vsync

(values after xrandr --newmode to be pasted from second line of generated values with cvt command from your own computer, don't copy from here. In other words, after writing xrandr --newmode in terminal, copy the output of cvt command from its second line excluding word Modeline upto its end and paste it after xrandr  --newmode

The type following:

xrandr --addmode VGA-0 "1280x768_60.00"

( get the right output by typing first " xrandr -q, here output is VGA-0 )

After these steps, resolution of 1280x768 will appear under the list of various resolutions available in display settings. This will remain listed for one session only. When computer is restarted, this will disappear. To make it appear permanently, we need to configure xorg.conf file and make this entry manually.


 3. In Mint, xorg.conf is not present by default and has to be created. This can be created only when x server is not working ie.  in console mode otherwise system will give error. Type these highlighted commands one by one:

Alt+Ctrl+F1 (switch to console mode)

Login by typing user name and password

sudo service lightdm stop (For Mint 12 Lisa users)   or   sudo service mdm stop (For Mint 13 Maya users)    

sudo X -configure (generates new xorg.conf file)

File with name xorg.conf.new will be created in Home folder. Although some error message will appear but file will be created. Just ignore that message.

Note: 1. Use only one of the commands (from sudo service lightdm stop or sudo service mdm stop) according to your distro edition. These are used to kill x server.

      2. In Mint 13 maya,  after sudo service mdm stop, Alt + Ctrl + F1 has to be pressed again.

 

4. To switch back to graphical mode, type:

sudo start lightdm (Mint 12 Lisa users)

sudo service mdm start (Mint 13 Maya users)

If above commands fail to bring back graphical mode, just restart your computer.

 

5. Open Home folder. Rename this file from xorg.conf.new to xorg.conf Open xorg.conf with text editor and make the following changes. Underline shows newly added lines

    Add Modeline in Monitor Section under each Identifier option. Example with 1600x900:

Section "Monitor"
        Identifier   "Monitor0"
        Modeline     "1600x900_60.00"  118.25  1600 1696 1856 2112  900 903 908 934 -hsync +vsync
        VendorName   "Monitor Vendor"
        ModelName    "Monitor Model"
EndSection

Section "Monitor"
        Identifier   "Monitor1"
        Modeline     "1600x900_60.00"  118.25  1600 1696 1856 2112  900 903 908 934 -hsync +vsync
        VendorName   "Monitor Vendor"
        ModelName    "Monitor Model"
EndSection

    Add modes in screen section in similar way as described above in each subsection (screen1, screen2) under the element Depth (Also for each depth). Example:

Section "Screen"
    Identifier "Screen0"
    Device     "Card0"
    Monitor    "Monitor0"
    SubSection "Display"
               Viewport   0 0
               Depth     1
               Modes   "1600x900"
    EndSubSection
    SubSection "Display"
                Viewport   0 0
                Depth     4
                Modes   "1600x900"
    EndSubSection
    SubSection "Display"
                 Viewport   0 0
                 Depth     8
                 Modes   "1600x900"
    EndSubSection

(Upto Depth 24)

EndSection

Section "Screen"

 Identifier "Screen1"
    Device     "Card1"
    Monitor    "Monitor1"
    SubSection "Display"
                Viewport   0 0
                Depth     1
                Modes   "1600x900"
    EndSubSection
    SubSection "Display"
                Viewport   0 0
                Depth     4
                Modes   "1600x900"
    EndSubSection
    SubSection "Display"
                 Viewport   0 0
                 Depth     8
                 Modes   "1600x900"
    EndSubSection

    (Upto Depth 24)

EndSection

 

6. Save this file and copy this file to /etc/X11/ by typing following command:

sudo cp xorg.conf /etc/X11

(assuming that xorg.conf is located at Home folder) or do it by graphically if you know.

 

Note: New resolution must be less than Maximum resolution that monitor can support. And care fully add those lines to each subsection Monitor0, Monitor1, Monitor2, Monitor3, Screen1, Screen2, Screen3, Screen4 . For Screen section, add entries for every Depth from 1, 2, 4, 8, 16, 24.