video modes and refresh frequency

[Pype.Clicker]

I've been showing clicker live to a friend today and he notice that "you're only supporting 60Hz ? your monitor seems blinking ..."

And he was damn' right... that system is usually able to do 100Hz refresh in that mode, and i'm stuck to 100Hz ... Anyone of you know of something to do be done to enable higher refresh rates (i'm using VBE on a nvidia GeForce-2 card)?

Also, if you have any knowledge on how one can retrieve "product & vendor" identification for the _monitor_ (i wish the VGA card would report them as sub-functions, or act as a bridge, but this is obviously not the case).

[Candy]

I've been showing clicker live to a friend today and he notice that "you're only supporting 60Hz ? your monitor seems blinking ..."

And he was d*mn' right... that system is usually able to do 100Hz refresh in that mode, and i'm stuck to 100Hz ... Anyone of you know of something to do be done to enable higher refresh rates (i'm using VBE on a nvidia GeForce-2 card)?

Also, if you have any knowledge on how one can retrieve "product & vendor" identification for the _monitor_ (i wish the VGA card would report them as sub-functions, or act as a bridge, but this is obviously not the case).

VESA supports retrieving monitor information about the refresh rate and the monitor capabilities, and I recall something called DDE being involved. I do know that it's a closed VESA standard that costs money to view, and that not enough information can be found in RBIL or on the internet.

You can try again though, my last check was 1.5 years ago. RBIL contains some information on it just below 10/4F05 (bank switch in VESA).

[Pype.Clicker]

you mean "Display Data Channel" ?

http://www.vesa.org/public/VBE/VBEDDC11.PDF

[Dex4u]

My understanding is you can only set it with vesa3, info in this doc
http://www.vesa.org/public/VBE/vbe3.pdf

Pixel clock has to be set correctly, = horizontal pixels * vertical pixels * refresh frequency.

[Pype.Clicker]

Quoting "VBE/Core" (which has cut'n'paste disabled >:()

"When calling application wishes to control the refresh rate for the mode being initialized, it must compuite a set of CRTC values and a normalized pixel clock that can be passed to function 4f02h when the mode is initialized.

Values can be taken from discrete VESA DMT timings or using the VM/Generalized Timing Formula.
You must then select the closetst pixel clock using VBE function 4f0bh"

(more about this under Using Refresh Rate Control)
1. Use VBE/DDC to obtain operational limits
2. use DMT or GTF to comute CRTC timings (...)
3. call 4f0bh to find actual pixel clock
4. re-run GTF formulas using resulting clock (if using GTF)
5. if enabling double-scabnned mode, set double-scan flag in CRTCInfoBlock
6. idem for enabling interlaced mode
7. call function 4f02h with bit "D11" set

(from VBE Core specification 3.0)

[CopperMan]

Does some one know where to get docz about DMT or GTF ?