Vol. 3C 35-253

MODEL-SPECIFIC REGISTERS (MSRS)

69EH

1694

MSR_

LASTBRANCH_30_FROM_IP

Thread

Last Branch Record 30 From IP (R/W)
See description of MSR_LASTBRANCH_0_FROM_IP.

69FH

1695

MSR_

LASTBRANCH_31_FROM_IP

Thread

Last Branch Record 31 From IP (R/W)
See description of MSR_LASTBRANCH_0_FROM_IP.

6B0H

1712

MSR_GRAPHICS_PERF_LIMI

T_REASONS

Package

Indicator of Frequency Clipping in the Processor Graphics (R/W)
(frequency refers to processor graphics frequency)

0

PROCHOT Status (R0)
When set, frequency is reduced due to assertion of external 

PROCHOT.

1

Thermal Status (R0)
When set, frequency is reduced due to a thermal event.

4:2

Reserved.

5

Running Average Thermal Limit Status (R0) 
When set, frequency is reduced due to running average thermal 

limit. 

6

VR Therm Alert Status (R0)
When set, frequency is reduced due to a thermal alert from a 

processor Voltage Regulator.

7

VR Thermal Design Current Status (R0)
When set, frequency is reduced due to VR TDC limit.

8

Other Status (R0)
When set, frequency is reduced due to electrical or other 

constraints.

9

Reserved

10

Package/Platform-Level Power Limiting PL1 Status (R0)
When set, frequency is reduced due to package/platform-level 

power limiting PL1.

11

Package/Platform-Level PL2 Power Limiting Status (R0)
When set, frequency is reduced due to package/platform-level 

power limiting PL2/PL3.

12

Inefficient Operation Status (R0)
When set, processor graphics frequency is operating below target 

frequency.

15:13

Reserved 

16

PROCHOT Log 
When set, indicates that the PROCHOT Status bit has asserted 

since the log bit was last cleared.
This log bit will remain set until cleared by software writing 0.

Table 35-37.  Additional MSRs Supported by 6th Generation Intel® Core™ Processors Based on Skylake 

Microarchitecture

Register 

Address

Register Name

Scope

Bit Description

 Hex

Dec