You can migrate live VMs between Intel processor-based servers but migration in a mixed CPU environment requires downtime and administrative hassle
A study commissioned by Intel Corp.
One of the greatest advantages of adopting a adopting a public, private, or hybrid cloud environment is being able to easily migrate the virtual machines that run your critical business applications—within the data center, across data centers, and between clouds. Routine hardware maintenance, data center expansion, server hardware upgrades, VM consolidation, and other events all require your IT staff to migrate VMs. For years, one powerful tool in your arsenal has been VMware vSphere® vMotion®, which can live migrate VMs from one host to another with zero
downtime, provided the servers share the same underlying architecture. The EVC (Enhanced vMotion Compatibility) feature of vMotion makes it possible to live migrate virtual machines even between different generations of CPUs within a given architecture.