Cyrix has made only incremental enhancements in its product line. The highly integrated MediaGX, which helped ignite the sub-$1,000 PC market last year, was upgraded in January to a version with MMX. The mainstream 6x86MX got a new name for its fastest version, now called the MII (pronounced M-two), but the chip itself gained no new features. It is now built with a more advanced process technology and runs at higher core and bus speeds. (Note that IBM also sells the 6x86MX and MII processors but has stuck with the 6x86MX name for all speeds.)

Because the 6x86MX delivers higher performance per clock cycle, Cyrix continues to use PR performance ratings, which are Intel-equivalent clock speeds, instead of the actual speed. Cyrix included the letters PR in the designation of the 6x86MX-PR266, and incorporated the PR rating into the CPU's name with the switch to the MII name: The MII/300 is a 233-MHz chip that Cyrix rates at PR300 (the performance equivalent of a Pentium II/300). Like AMD, Cyrix has reached the 333-MHz level (in integer application performance, not in clock speed), leaving both chip makers two speed grades behind Intel.

From the September 22, 1998 issue of PC Magazine