Intel Xeon E5-2660 v4 vs Intel Xeon E5-2690 v4: What is the difference?
CPU-Z Benchmarks on various Synology models - Hope this helps give a rough idea of the CPU power difference between models. Also included 2 other VMs running on Windows Hyper-V Server. :
Intel Xeon E5-2690 v3 Processor Benchmarks and Specs - GadgetVersus