The NX3100 is not on the vSphere HCL so i strongly suggest not to use it for virtualization in a VMware environment.  For the most bang for the bucks you can get a Powervault MD3220 which is a SAS storage and you can connect up to 4 Hosts in a redundant configuration if you like. If the hosts only used for testing vSphere virtualization get a DELL modell with the internal SD Cards so you dont need a local raid controller and disks. The R610 easily can take up 96GB of memory together with 2x6C x5645 XEONs. Keep in mind the the 4x1GbE are not enought for a redundant HA/vMOTION Cluster so you need an Intel 4 Port AddOn card as well together with SAS Card for the storage connection. If you would go the iSCSI route there is the MD3220i.  For VMware the vSphere Essentials Plus Package brings you 3x2 CPU and vCenter Essentials.The Package also includes HA and vMotion. Regards Joerg
I am looking to build a Test Lab and need some expert adice... We have £20,000 to spend and was thinking of the following. 2 x Dell R710 servers 1 x NX3100 with 4 x 2Tb Disks What OS should we be using on the Hosts and what VMWare version Package should we be using... and do you think the the Budget is workable. Finally any better suggestions as t the hardware we should use... I have heard that the Equallogic PS4100e would be better as a SAN than the NX3100. 
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