For the first
time since NVIDIA unveiled its nForce2 chipset more than a
year ago, VIA is in a very promising position. To
begin, AMD's Athlon 64 is upon us, bringing with it an
integrated memory controller that really equalizes the
advantage NVIDIA once enjoyed. In fact, the nForce3
and K8T800 chipsets generally fall within a percentage or
two of each other in performance benchmarks. VIA's
leg-up comes in the form of an encompassing feature
set. Its VT8237 South Bridge includes native Serial
ATA support and eight USB ports, compared to NVIDIA's
single-chip nForce3 that lacks Serial ATA, is limited to
six USB ports, and doesn't include the SoundStorm audio
processor that garnered so much acclaim.
K7 platform, KT600, isn't nearly as compelling.
Quite simply, it lags behind nForce2 in both the
performance and feature departments. Nevertheless,
it makes up a lot of ground lost by its predecessor,
KT400, which is particularly impressive because KT600
still relies on a single-channel memory architecture.
development from VIA doesn't revolve around Athlon 64 or
Athlon XP, though. This go 'round, the
Taiwanese firm is dedicating some attention to its Pentium
4 lineup. VIA knows full well that its principal
competition is the same company that manufactures the
Pentium 4. Yet, it's still gunning for the same
level of performance as Intel's 875P 'Canterwood' chipset.
PT880 is the product of a memory architecture re-design, a
feature-laden South Bridge, and a faster link between the
two chipset components. It isn't widely available just yet,
but when PT880 boards finally do arrive, representatives
from VIA expect that they will cost between $70 and $90.
How's that for performance on a budget?
VIA's PT880 Chipset
PT800 on Steroids
As we perused
the show floor of Computex in Taipei, Taiwan this year, we
noticed several motherboard vendors with PT800-based
designs. Prior to the show, we even managed to
secure Biostar's own PT800 board for testing. And
while the PT800 features support for Intel's 800MHz front
side bus, it only works with a single channel of DDR memory,
instantly crippling potential performance.
Incidentally, you can find PT800 boards online for less
the $50 dollars. We're more interested in enabling
performance, though, so when VIA called eager to
demonstrate its PT880 reference board, we gladly obliged.
Of course, the
primary difference between PT800 and PT880 is a second
64-bit memory channel, yielding 6.4GB per second of
theoretical bandwidth. Among the improvements
reportedly made to VIA's DualStream64 memory
controller, an enhanced data prefetch protocol, an
improved memory branch predictor, and tighter clock
timings are among the most notable. The controller
accommodates everything from DDR266 to DDR400 184-pin
modules, including Quad-Band Memory, projected to emerge
at some point in 2004. In turn, the PT880 North
Bridge interfaces with a Pentium 4 processor on a 400,
533, or 800MHz front side bus. Like Intel's 875P and
865 chipsets, PT880 fully supports Hyper-Threading
Technology. It also sports the obligatory AGP 8x
important distinction between PT880 and the value-oriented
PT800 is the path connecting the North and South Bridges.
Previously, all of VIA's chipsets featured a 533MB per
second interconnect dubbed V-Link. The latest
version, Ultra V-Link, runs at up to 1GB per second,
delivering more than enough throughput to the myriad of
devices that interface with VIA's VT8237 South Bridge.
South Bridge is a fairly recent development in itself.
VIA divides the South Bridge's feature set into three
categories: VIA Vinyl Audio, VIA DriveStation, and VIA
Connectivity. Vinyl Audio refers to the chipset's
integrated AC'97 codec, in addition to an optional onboard
7.1-channel Envy24PT processor. The DriveStation is
actually a two-channel parallel ATA controller, with
support for up to four devices and an integrated
two-channel Serial ATA controller equipped with RAID 0, 1,
and 0+1 support. When motherboards based on the
chipset ship, they'll include software to enable RAID
configurations "on the fly," or after an operating system
has already been installed on a single drive. VIA
Connectivity includes all of the other South Bridge
technologies, like USB 2.0 (eight ports), PCI slots,
10/100 Ethernet, and I/O devices.
VIA's PT880 Reference Motherboard