Processor Requirements

Any host used for Lync virtual machines should have a modern processor, which is 2.26 GHz or faster. This means that the CPU used should be manufactured at least from January of 2009 or later to achieve the required performance. From a planning perspective, the number of logical cores on the processor determines the maximum number of virtual machines that can run on the host. To fall within the Lync support boundaries, each virtual machine must have four dedicated CPU cores. This means that for a server that has eight cores, only two Lync virtual machines can run on the host, whereas a server with 16 cores can support up to four Lync virtual machines.

The number of cores is the important value here, not the number of physical processors. For example, two quad-core processors are equivalent to four dual-core processors. Both yield eight physical cores that can be used by virtual machines.