wolfgang+gnus20010708T172148@wsrcc.com (Wolfgang Rupprecht) writes:
> Is anyone else running a current xfree86 4.1.0 (2, Jun 2001) on a Sony
> Vaio 505tx?  Even though this same X11 binary runs fine my matrox
> cards and a 505ve it loops chewing up 100% of the CPU on the 505tx.  
> I would guess that something in the Neomagic NM2160 subsection (or
> something that only effects that chip) changed within the last few
> months.  (I haven't recompiled the server with "-g" and gdb-ed it
> yet.)

Problem solved.  The problem appears to have been some bad state in
the Neomagic NM2160 chip itself.  Reboots didn't clear it.  It took a
power off with battery+AC-adaptor pull to erase that state.

I finally started to suspect something like this when I rebooted into
the windows-something-or-other that the laptop came with.  After the
initial few seconds the LCD also blanked in the same way.  (Pounding
on the cntrl-alt-delete did get the machine to power off gracefully,
so that was a big hint that something bad was going on with the
screen.)

The important observation here was that the LCD stopped working after
a <function-key>-<escape> save to ram and power-down operation.  I
guess Sony has a bit of a timing problem where bad crap can be written
to the Neomagic.

Thanks also to Matthieu Herrb for the suggestion to try these options
which are known to help some versions of the NM2160:

    Option "XaaNoScanlineImageWriteRect"
    Option "XaaNoScanlineCPUToScreenColorExpandFill"

(I do see render problems with some types of fonts - perhaps this will
help with that.)

-wolfgang
-- 
       Wolfgang Rupprecht <wolfgang+gnus@dailyplanet.wsrcc.com>
		    http://www.wsrcc.com/wolfgang/
Coming soon: GPS mapping tools for Open Systems. http://www.gnomad-mapping.com/