Notes on how to get 800x600x16-color with a viper with 3.09 BIOS
THIS STUFF ALSO APPLIES TO GETTING W5186 VIPERS TO WORK WITH THE GENERIC
XF86_Mono driver, but you just replace vga16 with vga2 and use the XF86_Mono
driver instead of XF86_VGA16
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> From: v922539@coster.si.hhs.nl
> Folks, it's possible to get 800x600 in 16 sparkling colors on your "multi-
> million dollar ViperCard" with the following Xconfig setup: ...
> It might be that this setup only works correctly on ViperCards with an OAK
> addon VGA chip. Check your BIOS (Mine's 3.09)
> 
> vga16
>   Virtual	800 600
>   ViewPort      0 0
>   Modes	        "800x600" "640x480"
>   VideoRAM      2048

I beleive that should be videoram 256 , assuming that you have 256k of DRAM
for your vga chip, and 2048k of vram for the p9000, like other vipers and
P9000 cards (512 if you're lucky or 1024 if you have an Orchid).

>   ChipSet       "generic"
>   Clocks        25, 38   
>   ClockProg     "/usr/X386/bin/freq"
> # And last,  the database of video modes
> #
> ModeDB
> # OFFICIAL VESA Monitor timings + IBM Standards - TRY THESE FIRST
> # Contributor:          Thomas Roell [roell@sgcs.com]
> # Last Edit Date:       3/29/92
> #
> # name        clock   horizontal timing     vertical timing      flags
>  "640x480"     25      640  672  768  800    480  490  492  525
>  "800x600"     36      800  824  896 1024    600  601  603  625
> 	       38      800  840  1008 1032    600  600  603  630
>                40      800  840  968 1056    600  601  605  628
>                50      800  856  976 1040    600  637  643  666
> 

How 44k more little pixels with something like :

  Modes        "832x630" "800x600" "640x480"
  Clocks       25, 28, 38, 44
  ClockProg    "/wherevertheheckfreqis/freq" 28

ModeDB
#
# name        clock   horizontal timing     vertical timing      flags
 "640x480"     25      640  672  768  800    480  490  492  525
 "800x600"     38     800  840  1008 1032    600  600  603  630
 "832x630"     44     832  896  1056 1136    630  633  635  661

> From jbannist@uk03.bull.co.uk Tue Feb 22 05:29:59 1994
> ...I myself have a viper ( with 5186 ) and a friend of mine has an OAK chip.
> ... getting the X up on the viper with the OAK in 800x600x16
> colors but I am not sure of the procedure, ok here's it what I know so far
> 
> vga16
> 	Virtual 800 600
> 	ViewPort 0 0
> 	Modes "800x600" "640x480"
> 	VideoRAM 256
> 	Chipset "generic"
> 	Clocks 25, 38
> 	Clockprog "/usr/X386/bin/freq"
> 
> & the normal vesa monitor timings.
sounds OK

> Is the setting for the vram ok ?
I beleive so - I have yet to confirm the amount of ram available to the OAK
chip, since my data books don't containthe numbers I got for the viper-OAK
DRAM chips.
>, Why do you specify clocks in Mhz instead
> of KHz ? 
Xfree requires it , and limits the range of frequencies you can specify.

>, do I just modify the newfreq.c code I have obtained from
> sunsite.unc.edu to use in order the use the above Xconfig ?

Yes

> , if so which
> bits ? MUL to 1000000 ?

I suggest something like this:
diff -c newfreq.c newfreq.c.mhz
*** newfreq.c.khz       Thu Oct 28 08:54:18 1993
--- newfreq.c.mhz       Sat Feb 19 16:24:06 1994
***************
*** 255,266 ****
                return 1;
        }

!       freq=atol(argv[1]);
        if (argc > 2)
                quartz=atoi(argv[2]);

        if (freq<300l || freq>128000l) {
!               fprintf(stderr,"Pixel clock must be in the range [300-128000]\n);
                return 1;
        }
        if (freq>86000)
--- 255,266 ----
                return 1;
        }

!       freq=atol(argv[1])*1000;
        if (argc > 2)
                quartz=atoi(argv[2]);

	if (freq<300l || freq>128000l) {
!               fprintf(stderr,"Pixel clock must be in the range [1-128]\n");
                return 1;
        }
        if (freq>86000)
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