Hosts in an EVC cluster must meet certain requirements.

To enable EVC on a cluster, the cluster must meet the following requirements:

All virtual machines in the cluster that are running on hosts with a feature set greater than the EVC mode you intend to enable must be powered off or migrated out of the cluster before EVC is enabled.

All hosts in the cluster must have CPUs from a single vendor, either AMD or Intel.

All hosts in the cluster must be running ESX/ESXi 3.5 Update 2 or later.

All hosts in the cluster must be connected to the vCenter Server system.

All hosts in the cluster must have advanced CPU features, such as hardware virtualization support (AMD-V or Intel VT) and AMD No eXecute (NX) or Intel eXecute Disable (XD), enabled in the BIOS if they are available.

All hosts in the cluster should be configured for vMotion. See Host Configuration Requirements for vMotion.

All hosts in the cluster must have supported CPUs for the EVC mode you want to enable. To check EVC support for a specific processor or server model, see the VMware Compatibility Guide at

Any host added to an existing EVC-enabled cluster must also meet the requirements


Hardware vendors sometimes disable particular CPU features in the BIOS by default. This can cause problems in enabling EVC, because the EVC compatibility checks detect the absence of features that are expected to be present for a particular CPU. If you cannot enable EVC on a system with a compatible processor, ensure that all features are enabled in the BIOS.