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<A HREF="Oak.html"><EM>Information for Oak Technologies Inc. Chipset Users</EM></A>
 <b>:</b> <EM>Mode issues </EM><BR>
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  <H2><A NAME="3"></A>3. Mode issues </H2>

<p>The use of very high dot-clocks has a REAL negative effect on the
performance of the boards, due to its limited 80Mbit/sec, higher
dot clocks limit its ability to draw data into the
framebuffer. Thus expect better performance of a 72Mhz based mode
than on a 78Mhz based one (for example) where more bandwidth is
required for screen refresh.</p>
<p>It does not make much sense to use the highest clock (78 MHz) for
1024x768 at 76 Hz on a OTI087; the card will almost come to a
standstill. A 72 MHz dot clock results in 70 Hz which should be
acceptable. If you have a monitor that supports 1024x768 at 76 Hz
with a 78 MHz dot clock, a standard OTI087 based card is a poor
match anyway.</p>

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<A HREF="Oak.html"><EM>Information for Oak Technologies Inc. Chipset Users</EM></A>
 <b>:</b> <EM>Mode issues </EM><BR>
<b>Previous:</b> <A HREF="Oak2.html"><EM>XF86Config options </EM></A><BR>
<b>Next:</b> <A HREF="Oak4.html"><EM>Linear addressing</EM></A>



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