Arch Linux

tlawren

Member

From: Colorado, US

Registered: 2009-04-06

Posts: 80

DPI scaling on 4k and 2k dual setup, how to

I am trying to configure a 4k and 2k dual monitor setup and I am struggling with getting DPI scaling to work on the 4k display.  Right now, both monitors are operating at their native reolutions, so everything on the 4k display is tiny.  What I want is for the 4k to be scaled to say 120-150% and the 2k to run native.  Is this possible? 

I almost exclusively run i3 and apps such as Chromium, so I have been focusing mostly on adjusting X Server setting as directed in the HiDPI page on the Arch wiki.   The main problem I'm having is that I don't know how to make changes that only effect one monitor at a time.  Everything I do seems to effects both, which results in my making one monitor better while making the other worse.  I must be either doing something wrong or missing something.  If such a setup is possible, can I please get some advice on how to achieve it?

The current 20-nvidia.conf file I'm using is below.  This file includes only one Screen section (which I think might be the problem), but when I configure a second Screen section, i3 only shows up on one screen.  The second monitor remains a blank, black X screen with the X mouse cursor.  Is i3 limited to one session per X screen? 

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
    Option         "Xinerama" "0"
EndSection

Section "Files"
EndSection

Section "Module"
    Load           "dbe"
    Load           "extmod"
    Load           "type1"
    Load           "freetype"
    Load           "glx"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "DELL P2214H"
    HorizSync       30.0 - 83.0
    VertRefresh     56.0 - 76.0
    Option         "DPMS"
    Option         "UseEdiDpi" "false"
    Option         "DPI" "96 x 96"
EndSection

Section "Monitor"
	# HorizSync source: edid, VertRefresh source: edid
	Identifier     "Monitor1"
	VendorName     "Unknown"
	ModelName      "Lenovo Group Limited LEN LI2821wA"
	HorizSync       30.0 - 160.0
	VertRefresh     28.0 - 75.0
	Option         "DPMS"
	Option         "UseEdiDpi" "false"
	Option         "DPI" "90 x 90"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "Quadro K420"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "metamodes" "DVI-I-1: nvidia-auto-select +3840+0, DP-1: nvidia-auto-select +0+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection