jmarin@pyy.jmp.fi (Jukka Marin) writes:
> I got the XFree86 Mach_64 driver running on it, but when the display is
> updated (like when I move windows around), I see white stripes around
> the screen (kind of the effect that some CGA cards had 15 years ago :-)

You probably want to double and triple check the mode line you have
selected with the monitor specs.  Its not hard.  The semi-undocumented
numbers are just the timings in dot-clock units of the on-screen time,
the front-porch, sync pulse and back-porch of the H-sweep and V-sweep.
The monitor specs will put frequency limitations on the sweeps and
time constraints on the sync pulses and porches.  The dot clock should
be the lowest number that will get all your pixels up there at your
desired refresh rate.

Doing a good job of tweaking the modeline bought me a 10% higher
refresh rate without cranking up the dot clock.  If you are already
near the frame buffer's and/or monitors limit then cranking that will
just make your pixels fuzzier.  Pooching a modeline calculation and
not meeting a timing spec can cause the monitor to loose lock
spectacularly -- one-pixel wide white horizontal lines flashing
rapidly for only one frame etc, with surprisingly loud
snapping/sweaking sounds as the magnetic components of the monitor
complain loudly about the abuse.

-wolfgang
-- 
       Wolfgang Rupprecht <wolfgang+gnus@dailyplanet.wsrcc.com>
		    http://www.wsrcc.com/wolfgang/
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