Will vmotion work between two servers of different cpu cores/clockspeeds?

I have a set of hp servers that are HP dl380 E5620 G7s that are used as ESX 4.1 servers. I have them set up to do vmotion and to do fault tolerance. I've just received another set of servers, however they are E5649s.

The E5620s are 8 core dual proc while the E5649s are 6 core dual proc.

My gut tells me that these two different hardware specs won't be compatible with each other for the purposes of vmotion/fault tolerance, so I want to return them, but I need confirmation of it before I return them.

I'm simultaneously asking you guys as I'm contacting vmware as I can't find anything for or against this for compatibility issues on their site.

Yes, this combination will work. (BTW, the E5620 is a quad-core CPU - 8 total cores)

The CPU models you've listed are in the same family, so there aren't any major differences in the available instruction sets on the respective CPUs.

Here's the official VMWare Intel matrix. Your CPUs are listed as the "Intel 56xx series".

For systems that are less similar or of different CPU generations, the VMWare Enhanced vMotion Compatibility (EVC) masks can be set to allow a baseline CPU instruction set to work in a cluster.