October 31st, 2012 ~ by admin

Cyrix Joshua Processor – From Peppers to the Bible

Cyrix Joshua Sample

Perhaps one of the most confusing, and misreported processor stories is that of the Cyrix Joshua processor.  More correctly known as the VIA Cyrix III Joshua.  Cyrix began sampling this successor to the MII in 1999, a tumultuous time in Cyrix’s history, as they were in the midst of being sold to VIA by National Semiconductor.  The Joshua never made it into full production, being quickly killed off by the Centaur designed Samuel core. Centaur was the processor division of IDT which produced the Winchip series, bought by VIA only a month after their purchase of Cyrix.

Adding to the confusion was Cyrix bountiful use of code names for its upcoming products, with many seeming to overlap, change or be redundant.  Understanding the methodology of their naming will greatly increase ones understanding of the products.  Cyrix used a code name for the core of a processor, as well as a separate name for what application that core was going to be used in.  Just like Intel used the P6 core for the PII, Celeron, and Xeon, Cyrix intended its cores to be able to be used in several products.

In the late 1990′s Cyrix had two new cores under development.  The first was the Cayenne, an evolution of the 6x86MX/MII processor.  The Cayenne was essentially an MII, with a dual (rather then single) issue FPU, support for 3DNow! instructions, and perhaps most importantly, a 256K 8-way associative on-die L2 cache.  It retained the 7 stage pipeline of the MII, the 256 byte scratch pad L0 cache, an almost identical X-Y integer unit and the same 64K L1 cache.  Cyrix had had industry leading integer performance, but always lagged in the area of FPU performance.  The dual issue FPU was their attempt to help remedy this.  However, FPU intensive benchmarks, such as Quake 3, showed the Cayenne core to be about half as fast as a Celeron of equal rating (500MHz vs PR500 Cyrix).  Business apps, heavy in integer and light on floating point, showed the integer strength of the Cyrix, with a 400MHz Cyrix matching a 500MHz Celeron.

The Cayenne core was slated to be used in at least 3 different products.  The first was the MXi, this was the successor to the MediaGX and thus would be highly integrated, including a PCI Bus controller, SDRAM controller, MPEG/DVD acceleration, 2D/3D Graphics as well as audio capabilities. The Jedi was to be a socket 7 (Super 7 really) compatible processor based on the Cayenne core.  This was canceled in 1999 (nothing to do with potential lawsuits from Lucas Films as often was rumored).  The third use of the Cayenne core was the Gobi, this was to be a Socket 370 compatible processor and it is this version that was widely sampled, and benchmarked, by many hardware review sites, magazines, etc.  When VIA purchased Cyrix on June 30, 1999 the Gobi project was allowed to continue, MXi, and other projects were quickly shut down.  The Gobi codename did not fit with VIAs core naming scheme however, thus is was renamed.

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September 6th, 2012 ~ by admin

Intel vs. The World – The Infamous ’338 Patent

A Brief History

Long before the mess of Apple vs. Samsung (and seemingly everyone else), there was another famous company, with a patent in hand, that it seemed everyone was violating.  The issue of Intellectual Property (IP), and its associated patents has long been an issue in the technology business, and certainly in the business of CPU’s.  There are many many functions inside a CPU, different structures for handling instructions, memory access, cache algorithms, branch prediction etc.  All of these are unique, intellectual property.  It doesn’t matter if you implement them with a slightly different transistor structure, as long as the end product is relatively the same, there is the risk of violating a patent.  Patents are tricky things, and litigating them can be very risky.  You must balance the desire to keep competition from violating your IP, but at the same time minimize the risk that your patent is declared invalid.  This is why most cases end up in an out of court settlement, usually via arbitration.  Actual patent jury trials are fairly rare, as they are very expensive and very risky to all parties involved

Infringing?

In the early days (1970′s and early 1980′s) there was routine and widespread cross licensing in the industry.  Many companies didn’t have the fab capacity to reliably meet demand (IBM wouldn’t purchase a device unless it was made by at least 2 companies for this very reason) so they would contract with other manufacturers to make their design.  Having other companies manufacture your design, or compatible parts, also increased the market share of your architecture (8086, 68k etc).  For years AMD made and licensed most everything Intel made, AMD also licensed various peripheral chips to Intel (notably the 9511/2 FPU).  As the market grew larger, the competition increased, Intel (and others) began to have enough reliable fab capacity to safely single source devices.  Meanwhile other companies continued to make compatible products, based on previous licensing.  AMD notably made x86 CPU’s that ate into Intel’s market share. In the 1970′s Intel had cross license agreements with AMD, IBM, National, Texas Instruments, Mostek, Siemens, NEC and many others.

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Research

April 9th, 2010 ~ by admin

Cyrix MediaGX: From Cyrix to AMD – A bit a History

On February 20th of 1997 Cyrix announced the MediaGX processor, running at speeds of 120 and 133MHz. By June of that year they were up to 180MHz as production was ramped at National and IBM (see press release). These processors were based on the Cyrix M1 (5×86) architecture and integrated basic graphics, and audio functions. They were sold as a ‘PC on a chip’ for budget applications, with a bit of a budget performance.

Early MediaGX Marked Gx86 120MHz circa late '96

In October 1997 Cyrix announced plans for the Cayenne cored MXi, a follow on to the MediaGX. By 1999 National Semiconductor had made some samples of it, but thats as far as it got. This was also when National Semiconductor bought Cyrix, effectively ending Intel’s lawsuit against Cyrix over x86 licensing as National held an x86 license. The Media GX was bumped to 200 and 233MHz and MMX support was added.

National Semiconductor Geode 266MHz circa 2001 Sample

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