Hello. Client Operating System is not validated to operate on server hardware. It may or may not successfully run. Windows 7 and 8 user same drivers as Server 2008 and Server 2012 respectively and hopefully  Windows 10 will share same drivers with Server 2016.
I'm setting up a small render farm, and the hitch is that some of the animation software will not install on server OS.  Can Windows 7/8/10 (hopefully 10) be installed on the R610, or are there driver issues?  I'm looking at picking up several of these with the Dual Xeon X5550 CPUs IF I can install workstation software.
R610 + workstation OS?