Windows in Virtualbox does not start with more then 1 CPU

Hi ,

I’ve been trying to install a virtual Windows Server 2016 in Virtualbox. My host is Windows 10 Pro for Workstation.

I installed windows server2016 successfully, then i realized that I did not increase the number of CPU , I have AMD Ryzen 9 5900x so I can give 8/24 of Virtual Cores.

When I increase the number of CPU , Windows doesn’t start , when I decrease it was starting with no problem.

I opened bios and check virtualization settings. It was disabled by default. So I made it enabled. Restart it peacefully but got the same result!

I check stackoverflow and according some solutions I need to disable “Hyper-V” and “Windows Hypervisor Platform” from “Turn Windows Features on or off” so I did it.

It does not work either. After many hours of search , check forums , try something in bios I saw my bios was not updated.

When I update my bios , and make SVM enable again , the wasn’t any problem. Now I can continue to my job.

Here is the lesson , always update bios when you get a new computer.

Thanks ,