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<A HREF="ati.html"><EM>ATI Adapters README file</EM></A>
 <b>:</b> <EM>Current implementation of generic VGA support for non-ATI adapters</EM><BR>
<b>Previous:</b> <A HREF="ati3.html"><EM>Current implementation for ATI adapters</EM></A><BR>
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  <H2><A NAME="4"></A>4. Current implementation of generic VGA support for non-ATI adapters</H2>
<p>Support for generic VGA with non-ATI adapters is also implemented, but has
undergone only limited testing.
The driver will intentionally disallow the use of this support with ATI
adapters.
This support must be explicitly requested through an XF86Config ChipSet
specification.
This prevents the current generic driver from being disabled.</p>
<p>This driver's generic VGA support is intended as an extension of that provided
by the current generic driver.
Specifically, within the architectural bounds defined by IBM's VGA standard,
this driver will allow the use of any 256-colour mode, and any dot clock
frequencies both of which allow for many more mode possibilities.</p>
<p>The driver will enforce the following limitations derived from IBM's original
VGA implementation:
<ul>
<li>There can only be a set of four (non-programmable) clocks to choose from.</li>
<li>Video memory is limited to 256kB in monochrome and 16-colour modes.</li>
<li>Video memory is limited to 64kB in 256-colour modes.</li>
<li>Interlaced modes are not available.</li>
</ul>
</p>
 <HR NOSHADE>
<A HREF="ati.html"><EM>ATI Adapters README file</EM></A>
 <b>:</b> <EM>Current implementation of generic VGA support for non-ATI adapters</EM><BR>
<b>Previous:</b> <A HREF="ati3.html"><EM>Current implementation for ATI adapters</EM></A><BR>
<b>Next:</b> <A HREF="ati5.html"><EM>XF86Config specifications</EM></A>



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