Chipset - SOYO SY-K7ADA XP User Manual

Motherboard Description SY-K7ADA XP
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CHIPSET

ALi M1647 Overview
The M1647 is a high performance, high value North Bridge that supports
all Athlon family processors. Internally all 128-bit architecture with
optimization for S2K bus, DDR and AGP4X interface, the M1647 has
outstanding high system performance under all types of system operations.
The M1647 North Bridge, coupled with one of ALi's widely adopted PCI
South Bridge devices (M1535D+) provides a flexible and scalable
motherboard core logic solution to fill all applications.
The M1647 supports all Athlon family microprocessors. Processor bus
speeds of 66MHz to 133MHz are supported. This interface has 16 entries
for outstanding processor commands and system probe commands. This
interface supports FID change protocol for mobile purposes.
The M1647 can support up to 3.0 GB of SDRAM or DDR-SDRAM main
memory. Supports any combination of 66/100/133MHz memory bus
frequency and CPU bus frequency with minimized internal protocol
handshaking overhead, the M1647 provides a flexible system application.
In addition to dynamic memory power down, the M1647 also supports a
dynamic gated clock for the internal chipset logic circuitry, which will
reduce the system power consumption for mobile applications. The m1647
support the CAS-before-RAS refresh scheme and Self-refresh scheme
during normal mod and suspend mode, respectively.
The memory access controller plays a key role of dispatching the job to
the memory interface. By using a two-level dynamic arbitration scheme,
the M1647 fulfills multiple demanding sources that need access to the
main memory with balanced latency and maximum throughput. Another
important role of the memory access controller is the integration logic
between the AGP interface and main memory to support the AGP memory
address to physical memory address translate. To fulfill this function, the
M1647 uses 128 entries and 16 tags to implement a one level GART
(Graphic Address Re-mapping Table) scheme.
The M1647 supports all features of the AGP version 2.0 specification. This
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