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 www.centtech.com 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:
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.
- 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
- 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
- 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.
- 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.
- 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
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