Thanks & 2nd Sound Card, 2nd Video Card questions

Devin Carraway aqua at
Fri Jun 23 23:06:25 PDT 2000

On Fri, Jun 23, 2000 at 05:34:27PM -0700, Eric Eisenhart wrote:
> 1) XFree86 4.x, which does it by treating the two displays as if they were
> one large display -- this works well if both displays are the same
> resolution, but poorly if you have two different sized monitors.  I believe
> Devin is currently doing this with two different sized monitors.

	Definitely the way to go, at least until XiG gets to X11R6.4 with
xinerama.  Xinerama does push memory usage up quite a bit -- presumably by
pushing up the buffering and such requirements by a factor of 1.  I haven't
perceived any loss of performance with two cards over one, except when moving
windows along the boundary it's slightly slower (nothing to take offense at).

	X4 can operate in traditional multihead (mouse moves freely between,
apps live on one can can't pass between) or "xinerama" mode (monitors are
mapped onto arbitrary, possibly overlapping regions on a plane; windows map
onto the plane, and are displayed by whatever screen(s) happen to cover that

	The auto-configuration is good -- DCC support, or whatever it is,
interrogates the monitor about its sync ranges and sets up modelines to match,
so the whole arduous process of mode setup is gone (replaced with the somewhat
arduous process of downloading the thing, it being huge).  The
autoconfiguration is less good in xinerama mode, since you need to tell it
what spatial orientation you want, and which card to put where, this requiring
knowing the PCI IDs for the cards (use lspci).  I can provide a config file to
work off of if useful.

Devin  \ aqua(at), 1024D/E9ABFCD2;
Carraway \ IRC: Requiem  GCS/CC/L s-:--- !a !tv C++++$ ULB+++$ O+@ P L+++

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