GUIDE How to Fix Unknown CPU in About This Mac [Clover/OpenCore]

[EliteMacx86]

How to Change CPU Name in About This Mac

This guide describes how to fix unknown CPU Name in About This Mac. You can also use this guide to change the CPU Name in About This Mac. The guide works for both, Clover and OpenCore. By following this guide, you'll be able to fix the "Unknown CPU" in About This Mac.

Overview

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Although purely cosmetic, on a few systems, typically AMD and newer Intel CPUs does not have a native support in macOS/OS X. Due to this, the CPU isn't recognized correctly and is reported as "Unknown" Processor in About This Mac and in System Report. However, this does not has an impact in terms of performance, but it is still good to have the CPU name displayed instead of "Unknown". To fix the Unknown CPU in About in This Mac, follow the steps below.

Requirements

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Following are the requirements for fixing the unknown CPU in About This Mac on macOS. Please ensure you meet the requirements before proceeding with this guide.

CPU	macOS/OS X Compatible Intel/AMD CPU. See CPU Compatibility for more information
SMBIOS	Any compatible SMBIOS. See SMBIOS Compatibility for more information
Kexts	Lilu RestrictEvents
Tools	CPU-Name (If using the Manual method)

OpenCore

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If you're using OpenCore as a bootloader, follow the steps below to change the CPU Name.

Method #1: Manual Method

Using the manual method, you can change the CPU Name without the need for any extra tools. However, beginner users can find this method a bit difficult. New users are advised to use Method #2. To change the CPU Name using the "Manual Method" follow the steps below.

1. Download Lilu and RestrictEvents
2. Mount your ESP.
3. Copy both the kexts to EFI/OC/Kexts directory.

4. Open your config.plist and add the RestrictEvents.kext entry for the same in the Kernel>Add section of your config.plist.

5. Assuming the config.plist is still open, add revcpu=1 to the boot-args key under the 7C436110-AB2A-4BBB-A880-FE41995C9F82 UUID list in the NVRAM section of your config.plist.

TIP: You can also use NVRAM Variable and achieve the same effect. Simply add the following entry under the 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 UUID list in the NVRAM section of your config.plist.

• Key* = revcpu
• Value = 1
• Type = NUMBER

Key*	Value	Type
revcpu	1	NUMBER
revcpuname	Your CPU Name	STRING

NOTES:

• If you don't add any value for revcpuname, the CPU brand string will be taken from CPUID otherwise. If you want to use the original CPU brand string, we recommend you not add this key.
• If you're using revpatch=sbvmm (either via bootarg or the NVRAM), the CPU Name may change to the default, based on SMBIOS. You'll have to use the revcpuname=xxxx property. Where, the xxx represents your CPU Name.
• If you don't want to inject the property using Device Properties, you can use the same patch using revcpu=0 (Intel Default) or revcpu=1 (Non-Intel default) and revcpuname=xxxx in boot-args in your config.plist, where the xxxx represents your CPU Name. See adding boot args for more info.
• 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102:revpatch, 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102:revcpu, 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102:revcpuname and 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102:revblock NVRAM variables work the same as the boot arguments, but have lower priority.
• Do NOT use both, use either boot arg (recommended) or the NVRAM.

6. Depending on your CPU Core Count, set the Processor Type to 1537 (for 1, 2, 4 and 6 Core CPUs) and 3841 (for 8+ Core CPUs) under PlatformInfo>DataHub-Generic section of your config.plist
7. Save your config.plist
8. Restart your system for the applied changes to take effect. It is recommended to reset NVRAM twice at least.

Method #2: Using CPU-Name Tool

Using the CPU-Name tool from corpnewt, you can change the CPU Name. This method is a lot easier and more friendly for beginners. To change the CPU Name, follow the steps below.

1. Download Lilu and RestrictEvents
2. Mount your ESP.
3. Copy both the kexts from the RELEASE directory to the EFI/OC/Kexts directory. You'll also need to add the kext entries in the Kernel section of your config.plist.
4. Install Command Line Tools, if you haven't already.
5. Open the Terminal and execute the following commands. When prompted, enter your password.

#Clone CPU-Name
git clone https://github.com/corpnewt/CPU-Name

#Move to the directory
cd CPU-Name

#Modify permission
chmod +x CPU-Name.command

#Run CPU-Name
./CPU-Name.command

You'll see something similar to the following as an output of the operation:

Cloning into 'CPU-Name'...
remote: Enumerating objects: 146, done.
remote: Counting objects: 100% (63/63), done.
remote: Compressing objects: 100% (54/54), done.
remote: Total 146 (delta 32), reused 17 (delta 9), pack-reused 83
Receiving objects: 100% (146/146), 72.19 KiB | 1.60 MiB/s, done.
Resolving deltas: 100% (75/75), done.

6. Type 4 and press enter key to select the config.plist for changing the CPU Name.


and you'll see something like below



7. Drag and drop the config.plist from the EFI/Clover (Clover) and EFI/OC (OpenCore) directory to the CPU-Name Terminal Window and press enter key. If you have your EFI in some other directory, you can drag and drop the config.plist from your preferred location.


You'll see that the config.plist has been selected now. You can change the config.plist anytime, by pressing 4 key.

8. Type 3 and press enter key to clear CPU Name, Rev CPU, and Processor Type. This might be useful if you have used the script earlier or have tried to set the CPU Name manually.


9. Type 2 and press enter key to change the processor type



As you can see, there are currently 3 options to set the CPU Type which are described below. The CPU Type is set in SMBIOS section of your config.plist.

Processor Types

Options	Notes
1	Sets the Processor Type to 0x0601 (1537) in SMBIOS. Suitable for 1, 2, 4 and 6 Core CPUs.
2	Sets the Processor Type to 0x0F01 (3841) in SMBIOS. Suitable for 8+ Core CPUs.
L	Sets the Processor Type as per the System in SMBIOS

10. Depending on the CPU Core Count, select the appropriate Processor Type. If you're not aware of the CPU specification, it would be best to use L option as it will use your system value to determine the Core Count and set the Processor Type accordingly. In our case, we'll be using the option 2 as per the table, to set the Processor Type to 0x0F01 (3841).


Once the Processor Type is set, it will reflect the changes in the Main Menu. As you can see, now the Processor Type has been set to 0x0F01 (3841) as per the Processor Type Table.


11. Type 1 and press enter key to change the CPU Name


Here, you can either use the CPU brand string to set the CPU Name as per your system by using the L option (default option) or you can also manually enter the desired CPU Name.


12. Depending upon the option you would like to use, set the CPU Name. In our case, we would go with the manual route.


Once set, the new CPU Name will reflect in the Main Menu.

NOTE: If you have mistyped the CPU Name or want to change it again or want to start it over, you can use 3 to clear CPU Name, Rev CPU and the Processor Type.

13. Type Q and press enter key to quit CPU Name.


14. Quit Terminal
15. After performing all the above steps, restart your system for the applied changes to take effect. It is recommended to reset NVRAM twice at least.

NOTE: Regardless of the Method, either manual or using the CPU Name tool, the Core Count must be set correctly for AMD Systems to show the CPU brandstring otherwise, if set incorrectly, the CPU name may shown as Unknown.

Verifying the CPU Name

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The next step is to verify whether the CPU Name is changed or not. Follow the steps below to verify the CPU Name.

About This Mac

• Verify the CPU Name right next to the Processor in About This Mac

System Report

• Verify the Processor Name in About This Mac>System Report

 

[zano]

Hi guys, first of all i want thank you for your work, i just noted that on z690ud and b760m gaming x i wasn't able to see my intel core i5-12400F with the right name until i set processor type to 0 and added cpurev and cpurevname under 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 in NVRAM > UUID section (obviously i'm referring to manual mode)
maybe this can be useful for someone with the same problem

 

[EliteMacx86]

Hi guys, first of all i want thank you for your work, i just noted that on z690ud and b760m gaming x i wasn't able to see my intel core i5-12400F with the right name until i set processor type to 0 and added cpurev and cpurevname under 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 in NVRAM > UUID section (obviously i'm referring to manual mode)
maybe this can be useful for someone with the same problem

Could you provide your EFI to check further?

 

[zano]

Could you provide your EFI to check further?

sure

 

[EliteMacx86]

sure

The processor type seems to be set to 0. Can you reset NVRAM twice and check if you still see the CPU Name under macOS?

 

[zano]

The processor type seems to be set to 0. Can you reset NVRAM twice and check if you still see the CPU Name under macOS?

I followed accurately the guide and cleaned NVRAM tons of time (consecutively before booting) but only setting processor type to 0 after reading a comment of a random guy i was able to see "Intel Core i5 six-cores", than putting cpurev and cpurevname under 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 in NVRAM > UUID section i was able to set the right name.
I cleaned NVRAM twice and much at every change made but only setting processor type to 0 i was able to see a different name from "Unknown"; maybe the tool (cleannvram.efi) is not cleaning completely my NVRAM?
I will try asap with an older version of oc

 

[EliteMacx86]

I followed accurately the guide and cleaned NVRAM tons of time (consecutively before booting) but only setting processor type to 0 after reading a comment of a random guy i was able to see "Intel Core i5 six-cores", than putting cpurev and cpurevname under 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 in NVRAM > UUID section i was able to set the right name.
I cleaned NVRAM twice and much at every change made but only setting processor type to 0 i was able to see a different name from "Unknown"; maybe the tool (cleannvram.efi) is not cleaning completely my NVRAM?
I will try asap with an older version of oc

Maybe there are old preferences for the SMBIOS in Library/Preferences/System Configuration directory?

The thing is, with the processor type set to 0, it will always count the real value of the processor and the frequency as well such as i3, i5, i7, and i9. For making a name appear, the processor type must be set accordingly.

 

[zano]

Maybe there are old preferences for the SMBIOS in Library/Preferences/System Configuration directory?

The thing is, with the processor type set to 0, it will always count the real value of the processor and the frequency as well such as i3, i5, i7, and i9. For making a name appear, the processor type must be set accordingly.

With the z690ud i deleted old files from Library/Preferences/System Configuration and re-followed the guide but no changes, than with the same disk I tried to set the cpu name on a z690 gaming x ax with an i7-12700K and it functioned with processor type to 3842, but unfortunately in my case the only way i can set the cpuname correctly is putting revcpu and revcpuname under 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 in NVRAM > UUID and not under 7C436110-AB2A-4BBB-A880-FE41995C9F82 as per the guide, i'm probably wrong but i can't figure out where

 

[EliteMacx86]

With the z690ud i deleted old files from Library/Preferences/System Configuration and re-followed the guide but no changes, than with the same disk I tried to set the cpu name on a z690 gaming x ax with an i7-12700K and it functioned with processor type to 3842, but unfortunately in my case the only way i can set the cpuname correctly is putting revcpu and revcpuname under 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 in NVRAM > UUID and not under 7C436110-AB2A-4BBB-A880-FE41995C9F82 as per the guide, i'm probably wrong but i can't figure out where

Do note that revcpu and revcpuname is mandatory. Along with this, the processor type must be set.

Also, Thank you for bringing the attention. The UUID is corrected in the guide.

 

[Maxim0127]

Do note that revcpu and revcpuname is mandatory. Along with this, the processor type must be set.

Also, Thank you for bringing the attention. The UUID is corrected in the guide.

and how can I change the processor frequency if it is not displayed correctly?