VIA Apollo KT266A Chipset White Paper
VIA Apollo KT266A Chipset
Modular, highly scalable Socket A DDR chipset featuring
Performance Driven Design
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The VIA Apollo KT266A: Modular, highly scalable
Socket A chipset featuring Performance Driven Design
.
VIA Technologies Inc., the leader in Socket A chipset development, has again
raised the performance, feature set, and stability bar for the AMD Athlon
processor platform with the introduction of the VIA Apollo KT266A modular
DDR chipset. The first VIA chipset produced under the Performance Driven
Design philosophy, the VIA Apollo KT266A provides blistering memory
performance for today and tomorrow’s demanding applications.
The launch of the VIA Apollo KT266A solidifies VIA’s role as the leader in DDR
platform development. It also builds upon previous VIA chipset technology,
ensuring a stable, reliable, and scalable platform. Both new and proven
technologies that combine to form the VIA Apollo KT266A platform are
detailed below:
• Enhanced Memory Controller With Performance Driven Design:
The VIA Apollo KT266A features an enhanced memory controller,
designed with exceptionally high performance in mind. Supporting
DDR200/266 memory, the VIA Apollo KT266A provides lightning fast
access to system memory. Timings have been improved, resulting in
faster transfers between the synchronized Front Side Bus and Memory
Bus. Also, the new memory controller with Performance Driven Design
can burst up to eight Quad Words of data per clock, up from four in
previous designs. Data queues have also been deepened, allowing
faster and more efficient access to buffered data. The end result is the
industry’s fastest DDR memory controller.
• V-MAP: The VIA Apollo KT266A is part of the family of VIA Modular
Architecture Platforms (V-MAP). As a modular solution, the North and
South bridge of VIA Apollo KT266A are completely pin compatible with
current and future products, such as the VT8233C South Bridge with
integrated 3Com® Ethernet MAC, and the upcoming KM266 North
Bridge with integrated S3 graphics. V-MAP allows flexibility when
designing a system around the VIA Apollo KT266A chipset, enabling
OEMs and System Integrators to reach different market segments with
a single platform.
• High-Speed V-Link Hub Architecture: The VIA Apollo KT266A
makes use of VIA’s V-Link Hub Architecture, which provides a
dedicated 266MB/s bus between the North and South Bridge. Less
advanced chipsets use the 132MB/s PCI bus as a link, which must be
shared with all PCI peripherals.
• 200/266MHz DDR Front Side Bus Support: The VIA Apollo KT266A
supports the AMD Athlon/Duron S2K system bus, running at up to
an effective 266MHz. Offering up to 2.1GB/s of bandwidth, the 266MHz
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system bus perfectly complements the high performance DDR memory
subsystem and V-Link bus.
• AGP4X/2X Support: Providing up to 1GB/s in graphics bandwidth
with AGP4X technology, the VIA Apollo KT266A supports the latest in
video card technology. Additionally, it does not sacrifice AGP2X
compatibility like less advanced chipsets, allowing low cost graphics
products to be paired with low priced Athlon/Duron systems.
This white paper describes the features of the VIA Apollo KT266A chipset, as
well as the performance benefits that enable next generation computing for
high-performance desktops, workstations, and servers based on the AMD
Athlon and Duron processors
VIA Apollo KT266A Product Overview
The VIA Apollo KT266A consists of two separate chips: The 552-pin VT8366A
DDR North Bridge, and the 376-pin VT8233 or VT8233C V-Link South Bridge.
Both use standard PGA packaging to reduce the cost of production and allow
the use of standard heatsink solutions. The VT8366A is also a drop-in
replacement for the previous VT8366, allowing cost effective and seamless
upgrading of current motherboard designs. Future pin compatible products
featuring integrated graphics and other features will also become available,
enabling different market segments to be reached with a single platform
design. The following diagram outlines some of the basic features of the VIA
Apollo KT266A chipset.
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VIA Apollo KT266A North Bridge
The North Bridge of VIA Apollo KT266A (model number VT8366A) is the first
VIA product with Performance Driven Design. As such, it includes new
features and technology that assure the world’s highest memory
performance for the Socket A platform. Enhancements include tightened
timings on the S2K front side bus, deeper instruction and data queuing, and
the unique ability to burst up to eight Quad Words per clock.
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In addition to offering the fastest DDR memory controller available, the
VT8366A is also extremely flexible. Up to 4GB of DDR200 or DDR266 is
supported, including ECC and Registered modules. Also, PC100 and PC133
are supported, enabling platforms built upon the VIA Apollo KT266A to reach
very competitive price points. The VIA Apollo KT266A provides OEMs and
System Integrators with maximum flexibility and scalability to build a full
spectrum of high-performance and cost effective systems from mainstream
consumer and commercial desktops to high-end workstations and servers.
The VT8366A also supports the latest generation of AGP4X graphics cards,
providing up to 1GB/s of graphics bandwidth. For true workstation capability,
support for AGP Pro is included, providing additional voltage to high-end
CAD/CAM graphics cards. Despite these advanced features, the VT8366A
does not sacrifice support for older AGP2X models, enabling extremely low
graphics price points.
VIA Apollo KT266A South Bridge
The VIA Apollo KT266A is capable of interfacing, through its modular V-MAP
design, to any VIA V-Link South Bridge, including the VT8233 and VT8233C,
as well as future South Bridge designs. The VT8233 and VT8233C are highly
integrated network-ready South Bridges that feature two high-speed ATA-
100 IDE controllers (four IDE devices total), six USB ports, six PCI slots, Low
Pin Count (LPC) interface, and an I/O Advanced Programmable Interrupt

VIA KT266A是一款经典的主板芯片组，它由 VIA Technologies, Inc.（威盛科技股份有限公司）在2001年前后推出，专为Intel Pentium 4及早期的Prescott架构处理器设计。KT266A采用了Northwood与Southbridge两颗独立的晶片整合方案，其中Northwood负责CPU的接口、时钟调节和系统总线控制等功能，而Southbridge则处理I/O端口、IDE/ATA、SATA接口、USB、AGP、音频等外设通信和控制。 这款芯片组支持AGP 4x图形接口，对于当时的3D游戏和图形应用有一定的性能支持，并且提供了四个USB 2.0端口以及一个多声道音频控制器，方便用户连接外部设备和享受多媒体娱乐功能。此外，KT266A还支持双通道DDR内存技术，理论上可实现较高的系统内存带宽，对多任务处理和数据传输有显著提升。 然而，随着技术的发展，KT266A已经属于较为古老的主板芯片组，在现代高性能需求和更先进的接口标准面前，其性能和扩展性可能不再能满足当今许多用户的配置要求。如果您有关于新型号或更高级别的电气产品的问题，我们将很乐意为您提供帮助。