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WyoPBS

Member

From: Cheyenne, WY

Registered: 2007-10-05

Posts: 101

Website

can't change dpi on nvidia+hp flatscreen [SOLVED]

I buffed up my desktop box last week with a new nvidia card and hp 22" flatscreen monitor which recommends 1600x900 as the display resolution.  pixel width / physical screen dimensions work out to about 92dpi (X and Y) but for some reason it insists on 86x86, which renders fonts too small.

I have tried:
  -- adding "DPI 92x92" to my monitor section
  -- adding "NoDDC" "True" to the nvidia Device section
  -- starting X with startx --dpi 92 from the command line

none of this has any effect.  Here's my xorg.conf (keyboard and mouse sections removed for brevity)
------------
Section "ServerLayout"
    Identifier     "X.org Configured"
    Screen      0  "Screen0" 0 0
    InputDevice    "Mouse0" "CorePointer"
    InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

Section "Files"
    ModulePath   "/usr/lib/xorg/modules"
    FontPath     "/usr/share/fonts/misc"
    FontPath     "/usr/share/fonts/100dpi:unscaled"
    FontPath     "/usr/share/fonts/75dpi:unscaled"
    FontPath     "/usr/share/fonts/TTF"
    FontPath     "/usr/share/fonts/Type1"
    FontPath    "/usr/share/fonts/cyrillic"
EndSection

Section "Module"
    Load  "dri"
    Load  "glx"
    Load  "dri2"
    Load  "dbe"
    Load  "extmod"
EndSection

Section "DRI"
    Mode 0666
EndSection

Section "Monitor"
    Identifier    "hp2009m"
    HorizSync    24 - 85
    VertRefresh    48 - 76
    Option        "DPMS"
    Option        "DPI"    "92x92"
EndSection

Section "Device"
    Identifier  "nvidia"
    Driver      "nvidia"
    VendorName  "nvidia"
    BoardName   "GEforce"
    Option        "NoDDC"    "True"
EndSection

Section "Screen"
    Identifier "Screen0"
    Device     "nvidia"
    Monitor    "hp2009m"
    DefaultDepth    24
    SubSection "Display"
        Viewport   0 0
        Depth     24
        Modes       "1600x900"
    EndSubSection
EndSection
------------

See any obvious mistakes?  The log file does mention that NoDDC is ignored; there are no other warnings or errors.

Last edited by WyoPBS (2010-03-14 19:46:29)

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Peter B. Steiger
Cheyenne, WY

anonymous_user

Member

Registered: 2009-08-28

Posts: 3,059

Re: can't change dpi on nvidia+hp flatscreen [SOLVED]

Try this command for startx:

startx -- -dpi 92

Gen2ly

Member

From: Sevierville, TN

Registered: 2009-03-06

Posts: 1,529

Website

Re: can't change dpi on nvidia+hp flatscreen [SOLVED]

Well, you can tell the nvidia driver to ignore detection (see the DPI section in the Xorg page) which is what you might have to do.  But I'm wondering here if the dimensions you got for your screen weren't for the monitor itself (i.e. not the screen) which some manufacturers do.

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Setting Up a Scripting Environment | Proud donor to wikipedia - link

WyoPBS

Member

From: Cheyenne, WY

Registered: 2007-10-05

Posts: 101

Website

Re: can't change dpi on nvidia+hp flatscreen [SOLVED]

No, it was because I'm an idiot.  Several display cards / monitors ago I had similar resolution problems and I read that you can force a particular resolution by editing /etc/X11/xinit/xserverrc so that it reads
exec /usr/bin/X -nolisten tcp -dpi nnn
... which I did, years ago, and forgot about.  So of course it was obediently responding to my -dpi 86 instead of the correct 92 that it was detecting at startup.

I've only been doing Linux for about 12 years, maybe one of these days I'll actually learn something about it.

---

Peter B. Steiger
Cheyenne, WY

djgera

Developer

From: Buenos Aires - Argentina

Registered: 2008-12-24

Posts: 723

Website

Re: can't change dpi on nvidia+hp flatscreen [SOLVED]

with nvidia drivers use UseEdidDpi and DPI, for example:

Section "Device"
    Identifier     "Nvidia0"
    Driver         "nvidia"
    Option         "UseEdidDpi" "false"
    Option         "DPI" "92x92"
EndSection

Last edited by djgera (2010-03-14 20:04:11)