There are three VT-related settings in the BIOS setup as follows:
"Virtualization Technology Directed I/O" is support in the chipset for device assignment to a VM. Hyper-V doesn’t support that.
NOTE: The machine must be completely powered off (pull the AC cable to be sure) after you change these BIOS settings.
For example, VTx is a processor mode, that requires a cold boot of CPU. On normal reboot it does not power off.
NOTE: In some servers you even have to wait a minute before powering it on again. This is because of a security feature which ensures that that the virtualization setting can be written only once after power is applied to the processor. Typically the BIOS consumes this one write during BIOS POST before you can get to the BIOS config. On some machines that can take some time to drop power at the CPU.
In general, when changing the BIOS settings to enable Hyper-V:
tonysoper_MSFT edited Revision 4. Comment: + BIOS update as step 1
Ed Price - MSFT edited Revision 2. Comment: Minor edits and added tags. Great job!
This could apply to many other computers too. I've done some similar actions when I had to enable hardware virtualization for my PC.
Thanks, nice post :-)