GUIDE How to Fix TSC on macOS

[EliteMacx86]

How to Fix TSC on macOS

Overview

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The TSC (Time Stamp Counter) is responsible for ensuring that your CPU is running at its correct defined speed with the correct cores count. However, on some firmware (mostly HEDT/Server and ASUS Laptops) will not write the TSC to all cores which causes a slowdown and every running process is at extremely slow speed. Due to this, when attempting a clean install, the system may enter the boot loop state. To fix this issue, you have 3 options

Method	Purpose	Notes
CpuTscSync	For Laptops For some HEDT Systems	Automatic Sync. No customization is required.
VoodooTSCSync	For HEDT Systems	Automatic Sync. No customization is required.
TSCAdjustReset	For Skylake X/W/SP and Cascade Lake X/W/S	Need to define threads Customization is required.

 

[ebrunson]

How to Fix TSC on macOS

Overview

---

The TSC (Time Stamp Counter) is responsible for ensuring that your CPU is running at its correct defined speed with the correct cores count. However, on some firmware (mostly HEDT/Server and ASUS Laptops) will not write the TSC to all cores which causes a slowdown and every running process is at extremely slow speed. Due to this, when attempting a clean install, the system may enter the boot loop state. To fix this issue, you have 3 options

Method	Purpose	Notes
CpuTscSync	For Laptops For some HEDT Systems	Automatic Sync. No customization is required.
VoodooTSCSync	For HEDT Systems	Automatic Sync. No customization is required.
TSCAdjustReset	For Skylake X/W/SP and Cascade Lake X/W/S	Need to define threads Customization is required.

 

[ebrunson]

Was: The only way I can boot is using ResetTSCAdjust.efi tool on every boot or reboot. (Its a little bit of a pain!). The TSCAdjustReset.kext did not work for me on my Skylake CPU (i5-6600K).

Update:
I got TSCAdjustReset.kext to work by 1) removing all TSC-related boot-args and properly setting the IOCPUNumber in the kext (in my case it had to be 3 for the 4 threads in the CPU).

How:
"Open up the kext(ShowPackageContents in finder, Contents -> Info.plist) and change the Info.plist -> IOKitPersonalities -> IOPropertyMatch -> IOCPUNumber to the number of CPU threads you have starting from 0(i9 7980xe 18 core would be 35 as it has 36 threads total)." I used Xcode.

reference:

Fixing Sleep | OpenCore Post-Install

 

[ebrunson]

Was: The only way I can boot is using ResetTSCAdjust.efi tool on every boot or reboot. (Its a little bit of a pain!). The TSCAdjustReset.kext did not work for me on my Skylake CPU (i5-6600K).

Update:
I got TSCAdjustReset.kext to work by 1) removing all TSC-related boot-args and properly setting the IOCPUNumber in the kext (in my case it had to be 3 for the 4 threads in the CPU).

How:
"Open up the kext(ShowPackageContents in finder, Contents -> Info.plist) and change the Info.plist -> IOKitPersonalities -> IOPropertyMatch -> IOCPUNumber to the number of CPU threads you have starting from 0(i9 7980xe 18 core would be 35 as it has 36 threads total)." I used Xcode.

reference:

Fixing Sleep | OpenCore Post-Install

The final solution for me was to add the ResetTSCAdjust.efi to the Drivers folder so that it is automatically be invoked. The TSCAdjustReset.kext worked intermittently.

 

[EliteMacx86]

Not sure why you need such implementation for an i5-6600K Desktop CPU. Normally, its required for HEDT/Server and/or systems with a buggy BIOS.

 

[ebrunson]

Not sure why you need such implementation for an i5-6600K Desktop CPU. Normally, its required for HEDT/Server and/or systems with a buggy BIOS.

I would imagine it's the latter. I have two Skylake systems running Sonoma (MSI H110M MB (with i5 6600K) and HP 280 G2 (with i5 6500)) that both suffer this affliction and I now have the solution.

 

[EliteMacx86]

I would imagine it's the latter. I have two Skylake systems running Sonoma (MSI H110M MB (with i5 6600K) and HP 280 G2 (with i5 6500)) that both suffer this affliction and I now have the solution.

Could be possible.