Linux Hz Bug too?!?!?!?

[TheRealSkar]

Hi!
Im am new to linux and new to this board.
So greats@ all!
I have a small problem with my refreshrate.
My monitor supports at 1280x960 85Hz but
it only works with 60 Hz under X. I have the
nvidia driver installed and it works fine. In
the Mandrake 9 controll center i choosed
custom monitor und filled in the correct
sync rates. What else can i do?

thx so far

[Anthaus]

I'm having the same problem here. My monitor supports 1024x768 at 85hz, but I only get 60hz. This didn't happened in RH 7.2, but the problem arised when I switched to RH 7.3

I'm sure it's an XF86Config-4 trick, but I don't know where to start looking.

[Reeve]

I have the same problem, only in my case I have to use 60Hz for all modes to get them to work right. I recall other having problems like this with other things as well (like Win98 and the Linux framebuffer). Is it a hardware issue or is it just something funky going on in the drivers?

[Anthaus]

I bet it's the XF86Config-4 file.

Anyone?

[r0gu3]

Try setting your Horizontal Sync ranges in the monitor section of you XF86Config file to be that of your monitors :)

- r0gu3

[Anthaus]

Horizontal...

Will do. I would never imagine on my own that could be the problem.

BRB

[bwkaz]

If that doesn't help, maybe the VertRefresh setting? I don't know if you've tried that, but it would be worth a shot at least. Narrow it down to just the refresh rate you want, and see if that helps.

[Reeve]

I do have the correct settings for my monitor, but it doesn't seem to like anything but 60 Hz...
Oh well, maybe my monitor just sucks :D

[sanat]

Hey, it's not a bug, it's a feature. A feature that sucks if you want to use any resolution beyond the pedestrian VESA standard. XFree86 supplies a set of canned modelines compiled into the binary. Unfortunately, the only 1280x960 modelines supplied are at 60Hz. So you need to create your own modeline.

ColasXFree Modeline Generator (http://koala.ilog.fr/cgi-bin/nph-colas-modelines) will help you, but won't take you all the way there. Also, check out the XFree86 Video Timings HOWTO (http://www.ibiblio.org/mdw/HOWTO/XFree86-Video-Timings-HOWTO/index.html) which tells you about the math you can use to generate your own modeline.

When you are ready to test the modeline, open the /etc/XF86Config file, and insert your modeline in the Section "Monitor" area. Mine looks like this:

ModeLine "1280by960" 190.08 1280 1344 1600 1728 960 962 974 1000 #110Hz

Mine is running 1280 x 960 at 110hz

Then in the Section "Screen" area, specify that you wish to use your new modeline:

Subsection "Display"
Depth 24
Modes "1280by960"
ViewPort 0 0
EndSubsection

I had some problems getting my modeline right. I copied a modeline generated by the Colas site, but for some reason, the Nvidia driver complained that the 4th number minus the third number was greater than 256. Why, I don't know! But I added some to the third number and subtracted some from the 4th number till it was 256 and things are working fine. 110Hz is a great refresh rate for an all-in-one motherboard (Nforce)! Much better than WinCrap.

To generate your modeline, you need specific info on the capabilities of your monitor. You can find this info in your monitor manual or the manufacturer's website. You also need info on the capabilities of your video chip, which you can get from the /var/log/XFree86.log, where the GPU declares the rate of its pixel clock. You monitor probably has a lower pixel clock rate than your video GPU though. You need to know the lower of the two.

Also, there are many, many modelines compiled into XFree86, and I have read complaints on this board about X taking a long time to start up. It seems that the NVidia driver tests each and every compiled-in modeline -- whether it gets used or not. That takes too much time. My next project is to figure out how to compile my own Xfree without all those pre-fab modelines.