But I cannot find any reference to --cpuidset in the pdf-version of VirtualBox User Manual v.6.0.0. I do find references to --cpuidon page 144 and on page 120 I have found something similar called --cpuid-set
Ever consider the possibility that the "--cpuidset" might have changed to "--cpuid-set" and the forum posts here are older than the change?
You're right however there are 2 references in the UserManual.pdf to the "--cpuid" command that should be corrected to "--cpuid-set".
In any scenario, you should always try the "VBoxManage modifyvm" command with no parameters to check the correct syntax.
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