[...]
> > If you are talking RAM on the video card, that very much depends on the
> > card. For many of them the information that tells you how to find that out
> > just isn't available (together with the more complex stuff to really get
> > the card to work).
> I think it is probably possible to infer from the Win98 video mode and
> resolution how much ram, at least, is available. For some chipsets that
> are supported by XFree86, certain implementations (specific boards) still
> confuse it.
Infer how much != know how to use all of it
> > > > Also, Windows like to mess with IRQ's, DMA's and stuff that you'll no
> > > > neccsary agree to the same settings on Linux...
> > > The dot clocks, scan frequencies, and to a lesser extent the video mode
> > > are what's needed. These are the parameters that really need to be tuned
> > > manually often with XFree86 because you don't have the benefit of details
> > > of the particular card you have.
> > Those are parameters that depend on your _monitor_, not your video
> > card. And try to set up Win98 with an unknown monitor (i.e., a not PnP
> > one)...
> Actually I've had very little trouble setting up Win98 with various video
> cards and misc. monitors, even generic ones. Although it can take a
> little tweaking, the secret seems to be that the video card's BIOS and/or
> driver set's some reasonably middle video parameters that seem to work
> with typical monitors. (Of course cheap cards seem to assume cheap
> monitors and top of the line cards seem to assume a top of the line video
> monitor.)
I had _much_ more trouble with Win9[58] and a non-PnP monitor than with
Linux. As in works at 1024x768 in Linux, at most 400x320 in Win98, 320x200
in Win95. Strangely, works fine in WinNT at 1024x768. Go figure.
> With XFree86 conversely, I nearly always have to tweak, guess, and play
> around with things for a while before I get it right.
Not always. Lately much less than before.
> Part of my guess is that it's not just the chipset core, but other card
> details such as dram/gram/sdram, bus interface, clock chip, etc. that
> determine what the appropriate parameters are. The BIOS/Driver
> combination know what works well and XFree86 only has specific data
> points backed up with generalities. In other words, the driver knows
> that the card in question has cut corners to lower cost, or something,
> and that the chipset should be run at no more than X framerate, etc.
> Conversely, a newer card/monitor combination might drastically increase
> the speed compared to traditional versions of a chip and XFree86 would by
> default use the more conservative configuration.
That is part of the job the XFree86 people do: Get the data you outline,
and use it right. Note that very often the only information you have is
that the WeirdBrand (TM) video card has a XYZ model foo chip on it, nothing
more. Often not even the manufacturer's drivers work right in WinXX (Yep,
happened to me. Had to get a driver for the chip).
-- Dr. Horst H. von Brand mailto:vonbrand@inf.utfsm.cl Departamento de Informatica Fono: +56 32 654431 Universidad Tecnica Federico Santa Maria +56 32 654239 Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/