Although VMware software virtualizes the CPU, the virtual machine detects the specific model of the processor on which it is running.
Processor models might differ in the CPU features they offer, and applications running in the virtual machine can make use of these features. Therefore, it is not possible to use vMotion® to migrate virtual machines between systems running on processors with different feature sets. You can avoid this restriction, in some cases, by using Enhanced vMotion Compatibility (EVC) with processors that support this feature. See the vCenter Server and Host Management documentation for more information.