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Subject: Faster Video for Pentium Pros only
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Date: Mon, 07 Apr 1997 10:16:14 -0700
From: Amancio Hasty <hasty@rah.star-gate.com>
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I inserted the following instructions into the attach routine
of the bt848 driver. For now the placement of the instructions is not
that important. The following sets the first available memory range
register for my system and is specific for my graphic's card linear
buffer.

wrmsr(0x204, 0xf0000001  );
wrmsr(0x205, 0xf8000000 | 0x800);

My graphics card's linear frame buffer is at 0xf0000000 and is 4mb big.

I noticed that with mtv the maximum frame rate that I get playing 
an mpeg file is 23.8 frames/sec with the linear frame buffer set
to WC my maximum frame rate using the same mpeg file is 30.1 8)

The info on how to program the memory type range registers for 
the Pentium Pro is on the "Pentium Pro Developer's Manual
volume 3: Operating Systems Writer's Guide" . You may find the document
as 242692_1.pdf


	Enjoy,
	Amancio