I have a rather unusual question: What is the performance impact when you enable vt-x and you don't need it?

I ask this because all of the new servers I receive have this enabled by default in the BIOS and I wonder if this has any impact at all on the machine.

1 Answer 1


Perhaps there was a time early on in the development of VT-x when it would reduce performance by a single percentage or two but those times are long gone and I wouldn't expect to see any impact whatsoever now. Obviously if you're using any form of virtualisation disabling it will have enormous negative impact but I'm assuming you know that.

The reason it's on by default these days is that over 75% of all new systems are installed with one hypervisor or another, which need it.

  • 1
    "Hyper-V cannot be installed: Virtualization is disabled in the firmware." That's a pretty enormous negative impact. Apr 14, 2016 at 11:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.