VIA Apollo P4X266A Chipset White Paper
VIA Apollo P4X266A
Evolution of the world’s first DDR Pentium? 4 platform
featuring Performance Driven Design
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The VIA Apollo P4X266A: Evolution of the world’s first
DDR Pentium 4 platform featuring Performance Driven
Design
In its never ending quest to drive the advancement of PC platform
technology, VIA Technologies Inc. is constantly working to improve current
chipset designs. The latest fruits of this drive towards evolution is the VIA
Apollo P4X266A. Featuring the same performance enhancement technology
as the successful Apollo KT266A, the Apollo P4X266A pushes the
performance envelope even further, yet takes advantage of industry
standard DDR266 memory.
Latest in a long line of “A” branded chipsets, the VIA Apollo P4X266A follows
in the footsteps of previous successful designs. Starting with the VIA Apollo
Pro133A, and continuing with the VIA Apollo KT133A and KT266A, the “A”
line of performance chipsets have developed into a solid and well recognized
force in the marketplace. “A” series chipsets demonstrate VIA’s commitment
to the continual evolution of platform design.
The VIA Apollo P4X266A further expands VIA’s extensive line of Intel?
Pentium? 4 chipsets. VIA now offers Pentium 4 platform solutions from top
to bottom, with the VIA ProSavage P4M266 offering SMA graphics for the low
end, the VIA Apollo P4X266 offering mainstream discrete performance, and
the new VIA Apollo P4X266A covering the high end extreme performance
segment.
? Enhanced Processor Bus: The VIA Apollo P4X266A features an
enhanced processor bus interface that more efficiently takes
advantage of the quad pumped bus of the Intel? Pentium? 4
processor. Now, up to 12 instructions can be queued in the processor
bus interface, allowing the high speed 400MHz bus of current and
Pentium? 4 processors to run at optimal efficiency. This also reduces
latency between the processor and other peripherals and devices,
which improves overall system operation. The VIA Apollo P4X266A also
offers support for high bus speeds, allowing seamless upgradeability to
possible future processors.
? Performance Driven Design: Using the highly efficient memory
controller of the renowned VIA Apollo KT266A, the VIA Apollo P4X266A
offers exceptionally high memory performance. This is accomplished
through improved timings and deepened queues. Supporting up to
4GB of DDR200 or DDR266 memory, the VIA Apollo P4X266A provides
lightning fast access to system memory. Moreover, the VIA Apollo
P4X266A offers a highly developed AGP4X interface, ensuring the
highest possible graphics performance with a myriad of AGP4X
graphics accelerators.
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? V-MAP: The VIA Apollo P4X266A is part of the family of VIA Modular
Architecture Platforms (V-MAP). As a modular solution, the North and
South Bridge of VIA Apollo P4X266A are completely pin compatible
with current and future products. The VT8753A North Bridge of
P4X266A is pin compatible with the VT8753 of P4X266, and the
VT8751 of P4M266. Additionally, VT8753A can interface with three
separate pin-compatible South Bridges: The VT8233 offering VIA
Ethernet MAC, the VT8233C featuring 3Com Ethernet MAC, and the
VT8233A supporting the new ATA/133 drive standard. With this wide
range of pin-compatible products, up to six distinct chipsets are
possible for Intel? Pentium? 4 processors while using the same
motherboard design.
? High-Speed V-Link Hub Architecture: The VIA Apollo P4X266A
takes advantage of VIA’s high performance 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. V-Link greatly improves
data transfer rates when high-speed interconnect technologies such as
USB2.0, IEEE1394, and ATA/133 are implemented in a single system.
This white paper describes the features of the VIA Apollo P4X266A chipset
that enable next generation computing for high-performance desktops,
workstations, and servers based on Intel? Pentium? 4 processors.
VIA Apollo P4X266A Product Overview
The VIA Apollo P4X266A consists of two separate chips: The 664-pin
VT8753A DDR North Bridge, and choice of 376-pin V-MAP compatible South
Bridges, such as VT8233, VT8233C, or VT8233A. All chips use standard PGA
packaging to reduce the cost of production and allow the use of standard
heatsink solutions. The P4X266A is a drop-in replacement for the previous
VT8753, allowing cost effective and seamless upgrading of current
motherboard designs. The following diagram outlines some of the basic
features of the VIA Apollo P4X266A chipset.
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VIA Apollo P4X266A North Bridge
The North Bridge of VIA Apollo P4X266A (model number VT8753A) is the
second VIA product to feature Performance Driven Design. As such, it
includes new features and technology that assure the world’s highest SDRAM
performance for the Intel Pentium 4 processor. Up to 12 instructions can be
queued on the front side bus, hiding latency and increasing effective
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bandwidth. This contributes significantly to the VIA Apollo P4X266A’s high
memory performance.
The VT8753A retains the advanced features of previous DDR V-MAP chipsets,
such as flexible DRAM support. Up to 4GB of DDR200 or DDR266 is
supported, including ECC and Registered modules. The VT8753A is also
backwards compatible with PC100 and PC133, enabling platforms built upon
the VIA Apollo P4X266A to reach very competitive price points. The VIA
Apollo P4X266A 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 VT8753A 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, supplying additional voltage to high-end

VIA P4X266A是一款專為Intel 800MHz Pentium 4 (Prescott) 處理器設(shè)計(jì)的芯片組產(chǎn)品。它屬于VT82C559EB Northbridge 和 VT82C559D Southbridge 組合，支持AGP 4x/8x圖形加速接口、DDR SDRAM內(nèi)存控制器（最高達(dá)200MHz工作頻率）、IDE數(shù)據(jù)傳輸以及整合的AC'97音頻編解碼器等功能。這款芯片組還具備10/100Mbps Ethernet網(wǎng)卡控制功能和6個(gè)USB 2.0接口，能夠提供全面而穩(wěn)定的家庭或辦公環(huán)境下的I/O連接能力。 簡而言之，VIA P4X266A是一款適用于Pentium 4處理器的主板芯片組，集成了豐富的多媒體、網(wǎng)絡(luò)和擴(kuò)展接口，滿足了當(dāng)時(shí)中高端計(jì)算機(jī)平臺(tái)對(duì)于性能、兼容性和易用性方面的需求。用戶在選購相關(guān)主板時(shí)，若需搭配Pentium 4處理器并尋求較高性能表現(xiàn)和多元化接口支持，VIA P4X266A將是個(gè)不錯(cuò)的選擇。