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From: chau@caen.engin.umich.edu (Hin Fai Chau)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: 80387 25MHz & 33MHz Questions (Was : 80387 25MHz question)
Keywords: math coprocessor, clones
Message-ID: <1991Apr9.161838.23008@engin.umich.edu>
Date: 9 Apr 91 16:18:38 GMT
References: <298@sahara.cs.utexas.edu>
Sender: news@engin.umich.edu (CAEN Netnews)
Organization: University of Michigan Engineering, Ann Arbor
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I have similar questions but it is for 80387 33 MHz math coprocessor,
so I combine them with the previous article as follows:
 
1) How compatible are Cyrix, Weitek, and any others to Intel?  What
   other brands are available?  What technology are they based on,
   CMOS or NMOS?

2) What are the relative performance differences between them in terms
   of speed and accuracy?  Any known hardware bugs in those chips?

3) Are 80387 generally run at the same speed as the main CPU?
   (I was told that the 2/3 rule is generally true for 86 and 286 machines)

4) What are the relative costs between chips from different manufacturers?

5) Do I need a different coprocessor socket for Weitek 80387 chips?

6) Any clear winners?  Any good mail-order places to get them?

Any comments or suggestions will be greatly appreciated.
Thanks in advance!

Hin-Fai Chau
chau@caen.engin.umich.edu