# Monitor refresh rate.

## reasons

I have two dell 2209wa monitors that can run up to 75hz with custom settings. I figure I would just have to add a modeline in the monitor section of xorg.conf. I'm just not sure where it all goes. The timings are as follows:

```

Horizontal front porch: 48

Active horizontal pixels: 1680

Horizontal total: 1840

Horizontal sync width: 32

Horizontal sync polarity: -

Vertical front porch: 3

Active vertical lines: 1050

Vertical total: 1087

Vertical sync width: 6

Vertical sync polarity: +

Refresh rate: 75

```

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## Bones McCracker

It goes in the Monitor section.  There's a specific format.  Here's an example:

Modeline        "1400x1050"   155.80   1400 1464 1784 1912   1050 1052 1064 1090 +hsync +vsync

Here's some information from Xorg wiki:

http://www.x.org/wiki/FAQVideoModes

Also, see the man pages for these utilities, which can be useful when creating custom modelines:

xvidtune (this is a package you can emerge; it's a graphical utility)

gtf (this utility comes with xorg-server; it's a command-line utility, if I recall correctly)

Be careful: you can damage your monitor.

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## reasons

I've been messing with that all day I'm afraid. My monitor section looks like this"

```

Section "Monitor"

    Identifier     "Monitor0"

    VendorName     "Unknown"

    ModelName      "DELL 2209WA"

    HorizSync       30.0 - 83.0

    VertRefresh     60.0 - 76.0

    ModeLine       "1680x1050@75" 150.000 1680 1728 1760 1840 1050 1053 1059 1087 +hsync +vsync

    Option         "DPMS"

EndSection

```

Those values gotten from powerstrip in windows where I do have 75hz working.

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## RedSquirrel

The optimal refresh rate for that monitor is 60 Hz. It should be running at that without you having to do anything.

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## reasons

But it can do 75hz and gives me headaches at 60hz. I know there is the whole argument over what is necessary with LCDs, I've heard it all. In the end, I can't look at 60hz for long before I have to get up and do something else which isn't always an option.

The thing is, nvidia-settings has a 75hz option, but even with that selected and applied, nothing is differend and all is reported at 60hz.

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## Bones McCracker

Does it perform alright like that?  (Have you run any graphics benchmarks?)

Have you tried lower "recommended" resolutions that offer higher refresh rates?

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## RedSquirrel

Please post your /etc/X11/xorg.conf.

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## reasons

BoneKracker, I've gotten 1280x1024@75, but on a 1680x1050 monitor it looked horrible.

xorg.conf

```

Section "ServerLayout"

    Identifier     "Dual Head Configuration"

    Screen      0  "Screen0" 0 0

    Screen      1  "Screen1" Relative "Screen0" 1050 630

    InputDevice    "Keyboard0" "CoreKeyboard"

    InputDevice    "Mouse0" "CorePointer"

EndSection

Section "Files"

    ModulePath      "/usr/lib64/xorg/modules"

    FontPath        "/usr/share/fonts/misc/"

    FontPath        "/usr/share/fonts/TTF/"

    FontPath        "/usr/share/fonts/OTF"

    FontPath        "/usr/share/fonts/Type1/"

    FontPath        "/usr/share/fonts/100dpi/"

    FontPath        "/usr/share/fonts/75dpi/"

    FontPath        "/usr/share/fonts/terminus/"

    FontPath        "usr/share/fonts/corefonts"

EndSection

Section "Module"

    Load           "dbe"

    Load           "extmod"

    Load           "glx"

EndSection

Section "InputDevice"

    Identifier     "Mouse0"

    Driver         "mouse"

    Option         "Protocol" "auto"

    Option         "Device" "/dev/input/mice"

    Option         "Emulate3Buttons" "no"

    Option         "ZAxisMapping" "4 5"

EndSection

Section "InputDevice"

    Identifier     "Keyboard0"

    Driver         "kbd"

    Option         "XkbLayout" "gb"

    Option         "XkbModel" "pc105"

EndSection

Section "Monitor"

    Identifier     "Monitor0"

    VendorName     "Unknown"

    ModelName      "DELL 2209WA"

    HorizSync       30.0 - 83.0

    VertRefresh     60.0 - 76.0

    ModeLine       "1680x1050@75" 150.000 1680 1728 1760 1840 1050 1053 1059 1087 +hsync +vsync

    Option         "DPMS"

EndSection

Section "Monitor"

    Identifier     "Monitor1"

    VendorName     "Unknown"

    ModelName      "DELL 2209WA"

    HorizSync       30.0 - 83.0

    VertRefresh     60.0 - 76.0

    ModeLine       "1680x1050@75" 150.000 1680 1728 1760 1840 1050 1053 1059 1087 +hsync +vsync

    Option         "DPMS"

    Option         "RandRRotation" "on"

    Option         "Rotate" "CCW"

EndSection

Section "Device"

    Identifier     "Device0"

    Driver         "nvidia"

    VendorName     "NVIDIA Corporation"

    BoardName      "GeForce 9600 GT"

    BusID          "PCI:6:0:0"

    Screen          0

EndSection

Section "Device"

    Identifier     "Device1"

    Driver         "nvidia"

    VendorName     "NVIDIA Corporation"

    BoardName      "GeForce 9600 GT"

    BusID          "PCI:6:0:0"

    Screen          1

EndSection

Section "Screen"

    Identifier     "Screen0"

    Device         "Device0"

    Monitor        "Monitor1"

    DefaultDepth    24

    Option         "UseEDIDFreqs" "False"

    Option         "metamodes" "DFP-1: 1680x1050@75"

    SubSection     "Display"

        Depth       24

   Modes   "1680x1050@75"

    EndSubSection

EndSection

Section "Screen"

    Identifier     "Screen1"

    Device         "Device1"

    Monitor        "Monitor0"

    DefaultDepth    24

    Option         "UseEDIDFreqs" "False"

    Option         "metamodes" "DFP-0: 1680x1050@75"

    SubSection     "Display"

        Depth       24

   Modes   "1680x1050@75"

    EndSubSection

EndSection

```

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## Bones McCracker

 *reasons wrote:*   

> BoneKracker, I've gotten 1280x1024@75, but on a 1680x1050 monitor it looked horrible.

 

What resolutions are suggested by the documentation that came with the display?

What is the output of this command:

```
grep Modeline /var/log/Xorg.0.log
```

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## reasons

 *BoneKracker wrote:*   

>  *reasons wrote:*   BoneKracker, I've gotten 1280x1024@75, but on a 1680x1050 monitor it looked horrible. 
> 
> What resolutions are suggested by the documentation that came with the display?
> 
> What is the output of this command:
> ...

 

Recommended resolution is 1680x1050. There is no output for that command.

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## Bones McCracker

 *reasons wrote:*   

> There is no output for that command.

 

Oh.  That may be because you have this in xorg.conf:

```
Option         "UseEDIDFreqs" "False" 
```

Normally, you get a list of useful modes in the log file.  Then X will do its best to select an optimal one, unless something overrides it (like if you have a mode selected in xorg.conf, or if it has received information at the command line indicating a mode).

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## reasons

That's weird then, I still get nothing with it commented out.

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## poly_poly-man

 *reasons wrote:*   

> But it can do 75hz and gives me headaches at 60hz. I know there is the whole argument over what is necessary with LCDs, I've heard it all. In the end, I can't look at 60hz for long before I have to get up and do something else which isn't always an option.
> 
> The thing is, nvidia-settings has a 75hz option, but even with that selected and applied, nothing is differend and all is reported at 60hz.

 ummm... if an LCD monitor hurts your eyes at 60Hz, then you're either staring at a placebo or there's something seriously wrong with it.

You get 0 benefit from upping refresh rate.

btw, use read-edid (get-edid | parse edid on the command-line), throw that in the xorg.conf, then add Option NoDDC (I believe that's it... might take arguments) so it doesn't just look at your monitor.

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## RedSquirrel

Judging by the manual for your monitor, 1680x1050@75 Hz should have a pixel clock of 187 MHz. Your current Modeline says 150.

You can get pretty close to that 187 with gtf:

```
$ gtf 1680 1050 75

  # 1680x1050 @ 75.00 Hz (GTF) hsync: 82.20 kHz; pclk: 188.07 MHz

  Modeline "1680x1050_75.00"  188.07  1680 1800 1984 2288  1050 1051 1054 1096  -HSync +Vsync

```

```
$ gtf 1680 1050 74.9

  # 1680x1050 @ 74.90 Hz (GTF) hsync: 82.09 kHz; pclk: 187.82 MHz

  Modeline "1680x1050_74.90"  187.82  1680 1800 1984 2288  1050 1051 1054 1096  -HSync +Vsync
```

As BoneKracker warned above, you have to be careful with changing the refresh rate. I think it's better to leave it at 60 Hz and maybe tinker with the contrast & brightness, for example.

Edit: fixed typos

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