Intel Xeon E3-1220 Sandy Bridge Benchmarks and Review
Intel Xeon E3-1220 V6 Linux Benchmarks and Review
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 E3-1220 v3 vs Intel Core i5-4570 Benchmark, comparison and differences