VIA Cyrix III and VIA C3

Two processor design firm acquisitions and one winner. Two names and one winner. A bizarre story.

National Semiconductor acquired Cyrix some time ago and used IBM semiconductor manufacturing to produce the the Cyrix 6x86 and M2. They also used some 5x86 technology to produce the MediaGX which is still used today in some appliances under the Geode name. My evaluation AOLTV box used a 233 MHz MediaGX. The production version I bought at a fire sale is a 200 MHz Geode version, but this article, ironically, isn't about Cyrix at all. When Taiwanese chipset producer VIA came around and acquired Cyrix from NatSemi they also acquired the processor design firm Centaur Technology. VIA selected Centaur's WinChip over the Cyrix work-in-progress "Joshua" processor. Very quickly after Joshua failed VIA dropped the Cyrix technology altogether but kept the Cyrix name. Shortly after production of the first VIA Cyrix III chips based on WinChip, VIA dropped the Cyrix name and called their new family of processors the VIA C3. You can read some insider information at where they sometimes hint at their upcoming processor products.

Speaking of chipset producers, I heard that Taiwanese design firm SiS was going to produce a chipset with a Rise processor embedded in it but have nothing further.

Samuel, Samuel 2, Ezra, and Ezra-T are the model names of the current VIA C3 processor line. Let me summarize them:

  1. Samuel: The Samuel was the first to market and the chip I own is marked "VIA Cyrix III". The Samuel has 128KB of L1 cache and no L2 cache--many motherboards identify this chip as having no cache and it seems to perform that way. It requires a somewhat high 1.9 volts.
  2. Samuel 2: This chip is mostly the Samuel with 64KB of L2 cache. My vendor sold me a Samuel 2 chip that turns out to be an Ezra chip, so I can't comment on Samuel 2 and don't particulary desire to.
  3. Ezra: This is the current VIA C3. The chip I have is marked with "VIA C3" branding and performs exceedingly well at 1.35V. Some literature suggests this is built with 0.13-micron process but it is probably both 0.15 and 0.13 depending on when you bought it.
  4. Ezra-T: One web site suggests this is an Ezra with copper interconnects in FCPGA-2 format. According to the data sheet it appears to be the mobile version of the Ezra. If you get a 1GHz C3 it is unclear whether it is Ezra-T or Ezra.
  5. VIA e-Series: This processor is only available embedded on the fanless VIA Eden platform. The datasheets don't talk about this one so I don't have much to comment on. It's possible this may be the Ezra-T.
I bought an 866 MHz VIA C3 that the vendor said was a Samuel 2 model. The CPU identification programs report my VIA C3 as a C5B which the literature also suggests is a Samuel 2. The CPU identification string says "VIA Ezra" and the voltage used is 1.35V, which means Ezra. Either way the 866 MHz version I bought for $28 was so good I bought another. The 133 MHz external clock speed gives the processor a distinct advantage since it can access memory 33% faster than the fastest Socket-370 Celerons can. It runs very well without a CPU fan, too, making it the perfect bedroom computer. SiSoft Sandra gives it a "PR" rating of about 695 MHz which pretty much fits in the design constraints of the Centaur and the Bottomfeeder philosophy: you don't play 3D games on it but you do everything else exceptionally quickly.

Let me add a quick note on the economics of this processor. 866 MHz CPU for $28, all-in-one motherboard for $44, case for $30, 10GB hard disk for $45, 256MB memory for $25, and a modem or network card for $7. A total of $179 gives you a perfect bedroom computer. You can get the same thing in a complete Linux computer at Wal-Mart's web site for about $220.

The CeLeron has moved to Socket-478 so the Socket-370 platform may be going away but not too soon if the Wal-Mart PC and other VIA C3 products keep selling. Since the original VIA Cyrix III was a WinChip reworked for the P6 bus on Socket 370 it may be possible for VIA's Centaur folks to get the chip running on Socket-478 if they can implement the quad-pumped memory system used on Socket-478. We'll see.