ATI video controller

[jmk@plan9.att.com jmk@plan9.att.com]

	> board with a ics2494AM clock chip (but a BCT245 chip I take to be the ramdac).
the clock chip may be made by ICS but it contains an ATI specific table of frequencies.
there are, according to ATI, 3 possible clock chips on the mach32 which they call the
18811-[012] and i have seen a board with a clock-chip so labelled. the -[12] chips have
the same table. since i can't tell what the chip type is from software, the mach32 part
of aux/vga has a truncated table of frequencies whose entries match on all the chips:
 	25175000, 32000000, 40000000, 44900000, 65000000, 75000000
these frequencies match the common resolutions up to 1024x768. anything higher on the
mach32/64 requires using the accelerator and possibly programming the ramdac (this would
be a good thing to have as the mach64 is quite a zippy chip, hint).


	> The reason I'm appealing to the mailing list rather than spending (quite some)
	> time trying timing parameters is that the fact that aux/vga
	> always comes up with  "controller not in /lib/vgadb"  even though it
	> clearly is (and correctly so and at the correct 0xC0085 for
	> LOCAL BUS ATI ULTRA PRO  which happens as well to match the original
	> 0xC008F   ATI ULTRA PRO ).
	>	Does anyone know if the "controller not in lib/vgadb" message can mean,
	>	"yes, the controller is in the db, but I'm not happy with your description
	>	of it"?
no, it just means it couldn't find a matching address/string in the BIOS. this is
surprising given what you say. let's see the output of 'aux/vga -vp>somefile'.