MSR(Model-Specific Register) Additional, indirectly-accessible, registers containing control or status information about various aspects of the processor such as caches, performance counters, and the like.	These registers, accessible via the RDMSR and WRMSR instructions, were added with the Pentium and later-model 486 processors. C0000080h - AMD K6 - EXTENDED FEATURE ENABLE REGISTER
Size:	4 bits
SeeAlso: MSR(Model-Specific Register) Additional, indirectly-accessible, registers containing control or status information about various aspects of the processor such as caches, performance counters, and the like.	These registers, accessible via the RDMSR and WRMSR instructions, were added with the Pentium and later-model 486 processors. C0000081h,MSR(Model-Specific Register) Additional, indirectly-accessible, registers containing control or status information about various aspects of the processor such as caches, performance counters, and the like.	These registers, accessible via the RDMSR and WRMSR instructions, were added with the Pentium and later-model 486 processors. C0000082h


Bitfields for AMD K6 Extended Feature Enable Register:
Bit(s)	Description	(Table R0059)
 63-5	reserved
 4	disable L2 cache (K6-III)
 3      disable GEWBED (global EWBE)
 2      disable SEWBED (speculative EWBE)
 1      enable data prefetch
 0	system call extension (SYSCALL/SYSRET) enabled
	when disabled, both instructions generate an Undefined Opcode
	  exception
Note:	CPUID 80000001h should be checked to determine whether the SYSCALL
	  extension is implemented by the processor
SeeAlso: #R0060