Advanced Advice: Sandy Bridge / Sierra / SSDT performance

[haze295]

SOLVED



Hi everyone,

Updated my 2600k system to Sierra and learned that 12,2 iMac Board ID (best SSDT performance for 2600k) will not load in Sierra (causing blank screen and no video after apple logo). Verified by only changing this one item and it caused the issue, yet placing the iMac 14,2 board-id fixes the issue.

Therefore, I am using a 12,2 iMac SMBIOS, with 14,2 board-id. From what I can discern, intel power gadget shows similar wattage at lowest state, however it jumps up significantly under work load differently than in Yosemite (could be a Sierra thing). The main concern, is that CPU states looks drastically different and extremely limited on states.

Compared to my build using a 12,2 iMac with 12,2 board in Yosemite, I am only given:

CPU Low Frequency Mode.............: 1600 MHz

CPU Maximum non-Turbo Frequency....: 3400 MHz

CPU Maximum Turbo Frequency........: 3800 MHz

CPU P-States [ 34 (35) ]

CPU C3-Cores [ 1 3 6 ]

CPU C6-Cores [ 0 2 3 5 6 7 ]

CPU P-States [ (16) 33 34 35 ]

CPU C3-Cores [ 0 1 3 6 7 ]

CPU C6-Cores [ 0 1 2 3 4 5 6 7 ]

CPU C3-Cores [ 0 1 2 3 4 6 7 ]

CPU P-States [ 16 31 33 34 (35) ]

CPU C3-Cores [ 0 1 2 3 4 5 6 7 ]

bash-3.2#

My Yosemite build with 12,2 smbios and board led to something similar to 18,19,21,22,23,25,27,28,29,30,31,32,33,34,(35) set of states.

I am wondering if this will affect my systems performance, or power utilization (wattage)? Also if so is there another solution for former 12,2 iMac users?



Warm regards and thanks for any advice,

Haze

 

[haze295]

Update:

Here's what I came to find....

1. 12,2 was bugged within Sierra itself at 10.12.1. Video issue was solved in 10.12.2.
2. Reverted back to 12,2 board id and system now loads perfectly.
3. Re-ran ssdtPRGen.sh and compiled a new SSDT.
4. Reran apple intelinfo.kext and found a significant different in states:

CPU Ratio Info:

------------------------------------

CPU Low Frequency Mode.............: 1600 MHz

CPU Maximum non-Turbo Frequency....: 3400 MHz

CPU Maximum Turbo Frequency........: 3800 MHz

CPU P-States [ (16) 32 36 ]

CPU C3-Cores [ 0 2 6 7 ]

CPU C6-Cores [ 0 2 4 6 7 ]

CPU P-States [ (16) 23 32 36 ]

CPU C3-Cores [ 0 2 3 6 7 ]

CPU C6-Cores [ 0 1 2 4 5 6 7 ]

CPU P-States [ (16) 23 24 32 36 ]

CPU C3-Cores [ 0 2 3 4 5 6 7 ]

CPU P-States [ (16) 23 24 31 32 36 ]

CPU C3-Cores [ 0 1 2 3 4 5 6 7 ]

CPU P-States [ (16) 23 24 25 31 32 36 ]

CPU C6-Cores [ 0 1 2 3 4 5 6 7 ]

CPU P-States [ (16) 22 23 24 25 31 32 36 ]

CPU P-States [ (16) 22 23 24 25 30 31 32 36 ]

CPU P-States [ (16) 21 22 23 24 25 30 31 32 36 ]

CPU P-States [ 16 21 22 23 24 25 26 30 31 32 36 (37) ]

bash-3.2#

Hope this helps everyone else with this issue!

 

[questadilla]

This worked great on my 2500k Sandy Bridge system.. Thanks!

 

[outlook247]

@haze295 I just upgraded from Mavericks (10.9.5) to Sierra (10.12.5), my system will boot with 12,2 iMac SMBIOS and 14,2 iMac board-id (from post #1) but I get a black screen if they're both 12,2 iMac. In post #2, you stated your system booted fine in 10.12.2 when both smbios and board-id are set to 12,2 iMac; is this still the case in 10.12.5? Thanks!