|At the 1997 Computex in Taiwan newcommer to the x86 arena Centaur,
announced it started sampling a new x86 CPU, the C6. Centaur Technology
Inc. was a wholly owned subsidiary of Integrated Device Technology (IDT).
IDT, an established semiconductor company that produces specialty memories,
highspeed SRAM and embedded microprocessors. Designed by Centaur, manufactured
by IDT and IBM and sold by IDT, the C6 had a rather complex logistical background.
The CPU itself was anything but complex! Centaur had designed
a relatively simple 4th generation, 486 like CPU in just two years. It
has a Single Pipeline, in order execution, non superscalar CPU design.
But by using a large on chip cache, a refined pipeline design and using
a Pentium bus the C6 is able to achieve Pentium like performance. This
relatively simple design gave the C6 two advantages, small die size of
only 88mm2 (141 mm2 for the Pentium MMX and 162 for the K6) which means
lower manufacturing costs and low power consumption (7W at 225MHz). Centaur
did include the 57 MMX instructions, which was not implemented as good
as in other CPU's, but it helped increase performance in some applications.
On October 13 1997 the C6 was introduced at speeds of 180 and
200MHz. Later in April 1998 higher speeds of 225 and 240 were introduced.
The chip was introduced with the name C6, the same as the codename during
the design. To ensure endusers would know it was fully Windows compatible
the name was later changed in Winchip. This was to be the new familyname.
Performance of the C6 was not bad, integer performance was slightly
lower than that of a Pentium MMX, FPU perfomance on the other hand was
far behind. But then, IDT never claimed the C6 would be outperforming
a Pentium MMX. Selling point of the C6 was not top performance, but a
good price-performance ratio and low power consumption. It was therefore
primarily targeted at the low-cost desktop and laptop markets. However,
the market where the CPU would be used most was in the upgrade market.
The single voltage design made the C6 an ideal CPU for upgrading older
PC's that did not support split voltage. Manufacturers of upgrade products
like Evergreen used the C6 with a lot of succes in their products.
While performance was only average, the price was very acceptable.
Using the C6 in your system it could allow you to spend more on your graphics
card. A C6 system fitted with a Monster3D card would have surely outperformed
a Pentium MMX with a standard card.
Nice detail about the performance of the different models is that the
225MHz version outpeformed the 240MHz model! This was because the 225MHz
model used a 75MHz bus and the 240MHz model only a 60 MHz bus.
The C6 was manufactured with a four layer CMOS process technology
at 0.35 micron. Package type is PGA for use in Socket 7. Core voltage
is 3.3v and the total transistor count is 5,400,000. The CPUid for the
Centaur designed CPU's is 'CentaurHauls'.
Because of the limited production capabilities of IDT, at first
the C6 arrived to marked only in small numbers. Later, foundry agreements
with IBM secured a production in larger numbers.
Centaur refined the design of the C6, added 3D Now! and released
this revised design as the WinChip2. IDT released press release after
press release about soon to be introduced new versions of the WinChip
family. But no new chips were introduced and after a while it got quiet
around the WinChip. IDT meanwhile tried hard to find partners but eventually
the Centaur group was sold to VIA. VIA already bought Cyrix from Natinal
Semiconductors, the two CPU designers were merged and are now operating
under the wing of VIA.
C6 180MHz, 3 x 60MHz
C6 200MHz, 3 x 66MHz
C6 225MHZ, 3 x 75MHz
C6 240MHZ, 3 x 60MHz
IDT WinChip pictures