6x86MX > Cyrix6x86MX-PR166
Modified: May 27, 2005, 7:26 pm
Manufacturer:Cyrix
Model:6x86MX-PR166
Speed:150MHz
Type:MII
Data Code:9731
Introduced:1997
Transistors:6 Million
Package:296 CPGA w/ Integrated Heatspreader
Process:0.35 Micron 5 Layer
Architecture:32 bit CISC (RISC influenced) w/ MMX
Used in:Computers
Description:Cyrix entered the fifth generation processor
market with the 6x86 processor, formerly
projected as the M1. As a successful and cheaper
(often less than half the cost) alternative to
the Intel Pentium, it is pin- and voltage-
compatible with it. Cyrix gave it the 6x86 name
in reference to some of its more advanced
features, which it calls "sixth generation". In
reality, the processor is comparable in power and
architecture to the fifth-generation Pentium.

The MX went from PR166 to PR433, an impressive
spread. In the course of its life it went
from 0.35u to 0.18u and 2.9V to 2.2V.
The name was later changed from 6x86MX to MII
to compete with the Intel Pentium II.

The 6x86MX and MII are closely based on the
6x86 with a few additions:
MMX Support
Support for more multipliers
L1 Cache increased to 64K (from 16K)
Doubled the Branch prediction. (to 512 entries)
32-bit optimizations
256 bytes Intruction cache (pre-L1 cache)
-----------------------------------------
The Cyrix MX design was used by:
IBM
National Semiconductor
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Actual Speed: 150
Bus Speed: 60
Multiplier: 2.5
Fab'd By: IBM
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