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Significant power savings of the AMD Athlon processor 
only occur if the processor is disconnected from the system 
bus by the Northbridge while in the Halt or Stop Grant state.
The Northbridge can optionally initiate a bus disconnect 
upon the receipt of a Halt or Stop Grant special cycle. 
The option of disconnecting is controlled by an enable bits
in the Northbridge.

Program key features:
  Enables bus disconnect bit in the Northbridge.
  Full control under Clock Control (CLK_CTL)  MSR
  that determine the internal clock divisor when 
  Athlon system (S2k) bus is disconnected

Supported processors:
  AMD Duron, Athlon Processors Model 2,3,4 (w/ limitations)
  AMD Duron, Athlon, Athlon XP/MP Processors Model 6 & 
  upper

Supported chipsets:
  VIA KT133,  KT133A,  KLE133,  KX133,  KM266
         KT266,  KT266A,  KT333,  KT333 CF, KT400, KM400, 
         KT600
  nVidia nForce series,  nForce2
  SIS 730, 733, 735, 740, 745, 755, 746, 748
  AMD 751, 760, 761, 762