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Hyper-V with E cores on does not work 12th gen - My theories and can we make it work

Level 8
Hello everyone,
I'd like to bring up a topic that I'm seeing more and more and I am currently facing the same issue many people are facing.

I have 2 identical PCs
Intel i7 12th gen 12700k
Asus prime z690-p wifi d4

As a test I installed Windows Server 2022 on both machines.
No modifications to the BIOS (all cores enabled E and P) both machines ran Hyper-V with no issues for quite some time. Rebooting the machines gave no issues every component played happy with every other one. Happy days.

I then opted to take one machine and update the BIOS, since then all havoc occurs. I would reboot the machine it would freeze up, reinstall any OS same issue. Somehow I was finally able to get a new instance of Windows installed on the machine, I installed the Hyper-V role and when try to connect any VM I am presented with the error that the Hyper Visor isn't running.

I checked my BIOS I know Virtualization technology is running (since it was running fine prior to the BIOS update)

My theory on this is Asus released a BIOS update after 0605 and it is writing / wrote something to the mainboard that is instructing the E cores to do something that Windows does not like. Rolling back the BIOS does not fix the issue possible because it can not write back the old information correctly? The current working machine is on BIOS revision 0605 (which I will not update) and it works fine. I also installed the BIOS that was released today (version 2300) in hopes that the engineers at Asus figured out the issue but still no go.

Since the changelogs in the BIOS versions are not very detailed it's impossible to know what was changed.

There are two main questions I have

1) Can Asus validate the main differences between 0605 and any version above that to determine was was written to the BIOS that makes the E cores fail in Hyper-V and revert it?

2) Is there a way for us to force HV within Windows to allow the Hyper Visor to run while the E cores are present

I've tested this and I can confirm that it is related to the BIOS since the only thing that was changed from one machine to the other was the BIOS upgrade. Prior to the machine no longer working with E cores on both PCs were using 0605


Level 8
Anyone have any insight on this?

Figured it out it isnt related to any BIOS change.
It's ISO related.