FC2 - only 85Hz

[Jonathan Rawle]

Janis K wrote:

> hello
> 
> FC2 found my video cards as NVIDIA GeForce2 MX (generic) as it really is,
> and I have SONY Trinitron Multiscan E230 monitor 17'' (during the
> installation, FC2 recognized my monitor as SONY CPD E230), but FC2 Control
> Center shows ONLY 85Hz @ 1024x768 - why it is so?
> 
> on WinXP my monitor works with 100Hz @ 1024x768
> 
> how can I turn 100Hz @ 1024x768 on FC2?
> 

For some reason, modes with higher refresh rates are not defined in the
default X configuration. You need to add a ModeLine to your xorg.conf

>From a terminal, run xvidtune

Click "show" - a line of numbers will appear in the terminal

The first number after "1024x768" is the "Pixel clock" in MHz. The formulas
connecting the different frequencies are:

Horizontal sync = Pixel clock / HTotal
Vertical sync = Horizontal sync / VTotal

Note: HTotal and VTotal are larger than the resolution of the screen, as
indicated in xvidtune.

You can work out what you should change the pixel clock to in order to
obtain a 100Hz mode.

Now open your /etc/X11/xorg.conf in an editor. Find the "Monitor" section
and ensure that the specs for your monitor are correct - HorizSync (in KHz)
and VertRefresh (in Hz) MUST be right, or you risk damaging your monitor.
Check in the manual that they are correct. (I say this to cover myself -
you edit xorg.conf at your own risk).

Once you have done that, add an extra line in the Monitor section:
Modeline "1152x864"  144.00  1152 1216 1344 1600  864 865 868 900 +hsync 
+vsync

This is exactly the output from xvidtine with Modeline added to the
beginning (this is my example, yours will be different for 1024x768). Now
alter the pixel clock to the number you calculated.

Restart X, and now you should have a higher refresh rate.

Why they can't provide high refresh rate modes with X I don't know.

Hope that helps,


Jonathan