As you see on the above screenshot, Windows XP Professional x64 running on the 32-bit Windows 10 supported by a processor, Sempron LE-1100, lacking of AMD-V feature!
How can it be possible? As is known to us, both Legacy Mode and Long Mode use two different sets of system data structures to manage interrupts, paging and so forth. And that is impossible for Windows to switch mode from Legacy mode to Long Mode if without modify the NT Kernel! VMWARE Workstation is a platform virtual machine, I would not believe it would translate the x86-64 instructions onto the x86 instructions one by one. I wonder whether AMD64 processor has a secret or hidden mode besides the Legacy and Long Mode? And that secret mode is the associated mode attached with Legacy Mode rather than Long Mode. The VMMs just intercept the interrupts from the Guest OS, and emulated interrupts in Long Mode with software.
So I wonder is there a secret AMD64 mode without documented on the ISA manual? I am expected to your reply! Thank you in advance!