The Intel Xeon E5-2678 v3 was a server/workstation processor with 12 cores, launched in June 2015. It is part of the Xeon E5 lineup, using the Haswell-EP architecture with Socket 2011-3. Thanks to Intel Hyper-Threading the core-count is effectively doubled, to 24 threads. To further increase overall system performance, up to two Xeon E5-2678 v3 CPUs can work together in a multi-processor (SMP) configuration. Xeon E5-2678 v3 has 30 MB of L3 cache and operates at 2.5 GHz by default, but can boost up to 3.3 GHz, depending on the workload. Intel is making the Xeon E5-2678 v3 on a 22 nm production node using 2,600 million transistors. The multiplier is locked on Xeon E5-2678 v3, which limits its overclocking potential.
With a TDP of 120 W, the Xeon E5-2678 v3 consumes a lot of power, so good cooling is definitely needed. Intel's processor supports DDR3 and DDR4 memory with a quad-channel interface. The highest officially supported memory speed is 2133 MT/s, but with overclocking (and the right memory modules) you can go even higher. ECC memory is supported, too, which is an important capability for mission-critical systems, to avoid data corruption. For communication with other components in the computer, Xeon E5-2678 v3 uses a PCI-Express Gen 3 connection. This processor lacks integrated graphics, you might need a graphics card.
Hardware virtualization is available on the Xeon E5-2678 v3, which greatly improves virtual machine performance. Additionally, IOMMU virtualization (PCI passthrough) is supported, so that guest virtual machines may directly use host hardware. Programs using Advanced Vector Extensions (AVX) can run on this processor, boosting performance for calculation-heavy applications. Besides AVX, Intel is including the newer AVX2 standard, too, but not AVX-512.