CPU "AMD Ryzen 9 5900HX with Radeon Graphics" not supported ?

[iPk101]

Hello,

When I do a task, even if I set 8 core for the virtual machine, I get only one CPU to load with the task. Which make doing anything very slow...
I compared the same task from another computer (with the same virtual machine) with an Intel Processor and all CPUs are taking the load and the task is resolved almost instantly.
The problem is happening on a brand new laptop and I am trying to use a virtual machine and I think (from the log) that the CPU is not recognized by VirtualBox.
I checked the BIOS settings and it is definitively enabled (VM Mode for AMD).

From the vb log I found this entries :
00:00:01.781487 NEM: Warning! Unknown CPU features: 0x60277cb67f39fbf
00:00:01.783277 CPUM: No hardware-virtualization capability detected
00:00:01.785190 CPUM: fXStateHostMask=0x7; initial: 0x7; host XCR0=0x7
00:00:01.787512 CPUM: Matched host CPU AMD 0x19/0x50/0x0 AMD_Unknown with CPU DB entry 'AMD FX-8150 Eight-Core' (AMD 0x15/0x1/0x2 AMD_15h_Bulldozer)
00:00:01.787573 CPUM: MXCSR_MASK=0x2ffff (host: 0x2ffff)
00:00:01.787583 CPUM: Microcode revision 0x0A50000B

I attached the complete log as I saw this being requested commonly on this forum.
In the logs I just started the OS and stopped it.
I am on a Windows 10 and I am running a virtual machine with Windows 10.
Thank's in advance for your feedback.

Best regards,

[scottgus1]

Hyper-V is enabled. See HMR3Init: Attempting fall back to NEM (Hyper-V is active)

[iPk101]

Amazing !
Thank you for the super useful answer!

PS: I was testing the option "Microsoft Defender Guard" in the AV of Microsoft and that was the source of the problem (it virtualize a broswer). I uninstalled the feature from Windows and after that the vm is working super fast!

[scottgus1]

Great! Glad you're up and running.