Got it! (was Re: [CLUE-Tech] X resolution)

[Matt Gushee]

On Fri, May 30, 2003 at 02:58:58PM -0600, Michael Robbert wrote:
> 
> You are defnining a 24 bit color depth which should work with your 
> memory, but I think that it is actually using 32 bits per pixel which 
> will go over your actual memory. For right now I'd try to set your 
> config to use a Depth of 16 bits and see if that works. If it does then 
> try to find out how to make 24 bits only use 24 bits.

Okay, here's what I found out (mostly just regurgitating the docs
here--I don't really understand this):

Some video cards, including mine, can use either a packed 24-bit or a
sparse 32-bit framebuffer layout. Evidently my card tries to use 32 by
default, which accounts for X using 32 bits for 24-bit color. The
setting that controls this is 

  -fbbpp

on the command line, or

  DefaultFbBpp

in XF86Config. So I put

  DefaultFbBpp  24

in my config, and now I have 1280x1024 with 24-bit color. Yee-haw!

Many thanks to those who helped. Now if somebody can just explain to me
the significance of the framebuffer layout, I'll be happy!

-- 
Matt Gushee                 When a nation follows the Way,
Englewood, Colorado, USA    Horses bear manure through
mgushee at havenrock.com           its fields;
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                            --Lao Tzu (Peter Merel, trans.)