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To: Charles Henrich <henrich@crh.cl.msu.edu>
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Subject: Re: Faster X Updates 
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Date: Wed, 19 Nov 1997 10:13:31 -0800
From: Amancio Hasty <hasty@rah.star-gate.com>
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For pentium pro and pentium II systems you can enable write combine 
for your display buffer . this is what I do for my matrox millenium
frame buffer. Do a netsearch on fastvid for an explanation on 
PCI write combinining . 

	wrmsr(0x204, 0xf9800001);
	wrmsr(0x205, 0xffc00000 | 0x800);

You can get the details on the above instructions from the Pentium Pro's
developers manual, chapter 11. the full manual is at:
ftp://rah.star-gate.com/pub/242692_1.pdf

The above hack can boot your frame buffer thruput from 20MB/sec to 
90MB/sec

	Good Luck,
	Amancio