Intel 64 and IA-32 Architectures Software Developers Manual Volume 3B, System Programming Guide Part 2

Table Of Contents
Vol. 3 B-135
MODEL-SPECIFIC REGISTERS (MSRS)
CDH 205 MSR_FSB_FREQ Shared Scaleable Bus Speed. (RO)
This field indicates the scaleable bus clock
speed:
2:0 101B: 100 MHz (FSB 400)
001B: 133 MHz (FSB 533)
011B: 167 MHz (FSB 667)
133.33 MHz should be utilized if performing
calculation with System Bus Speed when
encoding is 101B.
166.67 MHz should be utilized if performing
calculation with System Bus Speed when
encoding is 001B.
63:3 Reserved
E7H 231 IA32_MPERF Unique Maximum Performance Frequency Clock
Count. (RW). see Table B-2
E8H 232 IA32_APERF Unique Actual Performance Frequency Clock Count.
(RW). see Table B-2
FEH 254 IA32_MTRRCAP Unique see Table B-2
11EH 281 MSR_BBL_CR_
CTL3
Shared
0 L2 Hardware Enabled. (RO)
1 = If the L2 is hardware-enabled
0 = Indicates if the L2 is hardware-disabled
7:1 Reserved.
8 L2 Enabled. (R/W)
1 = L2 cache has been initialized
0 = Disabled (default)
Until this bit is set the processor will not
respond to the WBINVD instruction or the
assertion of the FLUSH# input.
22:9 Reserved.
Table B-9. MSRs in Intel Core Solo, Intel Core Duo Processors, and Dual-Core Intel
Xeon Processor LV (Contd.)
Register
Address Register Name
Shared/
Unique Bit Description
Hex Dec