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<A HREF="Mach32.html"><EM>Notes for Mach32 X Server</EM></A>
 <b>:</b> <EM>Supported Cards, RAMDACs, and Bits Per Pixel</EM><BR>
<b>Previous:</b> <A HREF="Mach32.html"><EM>Notes for Mach32 X Server</EM></A><BR>
<b>Next:</b> <A HREF="Mach322.html"><EM>XF86Config options</EM></A>


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  <H2><A NAME="1"></A>1. Supported Cards, RAMDACs, and Bits Per Pixel</H2>
<p>The base support in the Mach32 X server is for 8 bpp, with a dot clock
of up to 80 MHz.  At present 15/16 bpp is supported on only three of the
many RAMDACs; however those three cover the most commonly sold cards.</p>
<p>
<pre>
 RAMDAC      Max Dot Clock   BPP   Max Resolution   Video RAM Required
--------     -------------   ---   --------------   ------------------
Default           80MHz       8      1280x1024i            2Mb
Default           80MHz       8      1024x768              1Mb

ATI68875         135MHz       8      1280x1024             2Mb
ATI68875          80MHz      16      1024x768              2Mb

AT&amp;T20C49x        80MHz       8      1024x768              1Mb
AT&amp;T20C49x        40MHz      16       800x600              2Mb

BT481             80MHz       8      1024x768              1Mb
BT481             40MHz      16       800x600              2Mb
</pre>
</p>
<p>The RAMDAC is reported when you run the Mach32 X server with the
"<code>-probeonly</code>" command line option, or can be specified in the
XF86Config file.</p>
<p>The ATI68875 (or the TLC34075) is used on the Graphics Ultra + and
the Graphics Ultra Pro.  The Brooktree 481 is used on most Graphics
Wonder cards.  The AT&amp;T20C491 is used on many of the OEM cards
that are built into component systems.</p>
<p>The BIOS detection unfortunately lumps the BT481 and the AT&amp;T20C49x
together, while they require different configuration controls in 16 bit
mode.  SuperProbe can tell the difference, and will report which it finds.
In the server itself, the BT481 is considered the default value.  If you
have an AT&amp;TC49x RAMDAC on your card you will have to include the Ramdac
entry in the XF86Config file as below.</p>

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<A HREF="Mach32.html"><EM>Notes for Mach32 X Server</EM></A>
 <b>:</b> <EM>Supported Cards, RAMDACs, and Bits Per Pixel</EM><BR>
<b>Previous:</b> <A HREF="Mach32.html"><EM>Notes for Mach32 X Server</EM></A><BR>
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