Cyrix, by this time, was a major player in the alternative processor market. They had been around since 1992, with their release of the 486SLC. By 1995, they had their own 5×86 processor and it was considered the only real competition to the AMD counterpart. But, they released their 6×86 in 1995. It was designed to go head to head with Intel’s Pentium processor. Dubbed “M1″, the chip contained two super-pipelined integer units, an on-die FPU, and 16 KB of write-back cache. It used many of the same techniques internally as the Intel and AMD chips to increase performance. Like AMD beginning with their K5 (see below), Cyrix used the P-rating system. It came in PR-120, 133, 150, 166 and 200 versions. Each rating had a “+” after it, indicating that it performed better than the corresponding Pentium. But, did it?

Cyrix had had a reputation for lagging in the area of performance, and the M1 was not an exception. The chip used a weaker FPU than both AMD and Intel, meaning it could not keep up with the competition in areas such as 3D gaming or other math-intensive software. On top of that, the chip had a reputation for running hot. Users had to get CPU fans that could keep these hot processors cool enough to run stably. Cyrix tried to combat this issue with the 6x86L processor. This “low power” processor made use of a split voltage (3.3 volts for I/O and 2.8 volts internally).

MediaGX (1996)

MediaGX was Cyrix’s answer to low-cost entry level PC’s. Making use of a standard x86 processor core, the chip lowered the cost of PCs using it by integrating many of the common PC components into the chip itself. MediaGX had integrated audio and video circuitry, as well as circuitry to handle many of the common tasks normally handled by chips on the motherboard itself. The CPU spoke directly to a PCI bus and DRAM memory, and the video was rather high-quality SVGA (for the time). It could support up to 128 MB of EDO RAM in 4 separate memory banks, and the video sub-system could support resolutions of up to 1280x1024x8 or 1024x768x16.

The integration of MediaGX was actually spanned across two chips: the processor itself and the MediaGX Cx5510. The chip requires a specially designed motherboard. It is not Socket 7 compatible. As a result, it is really an outsider in relation to the other processors we were discussing, but being that it was on the timetrack of history for CPUs, it bears mentioning.