The Intel Xeon E5-2643 is a server/workstation processor with 4 cores, launched in March 2012. It is part of the Xeon E5 lineup, using the Sandy Bridge-EP architecture with Socket 2011. Thanks to Intel Hyper-Threading the core-count is effectively doubled, to 8 threads. To further increase overall system performance, up to two Xeon E5-2643 CPUs can link up in a multi-processor (SMP) configuration. Xeon E5-2643 has 10 MB of L3 cache and operates at 3.3 GHz by default, but can boost up to 3.5 GHz, depending on the workload. Intel is building the Xeon E5-2643 on a 32 nm production process using 1,270 million transistors. The multiplier is locked on Xeon E5-2643, which limits its overclocking capabilities.
With a TDP of 130 W, the Xeon E5-2643 consumes a lot of power, so good cooling is definitely needed. Intel's processor supports DDR3 memory with a quad-channel interface. 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 system, Xeon E5-2643 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 E5-2643, 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) will run on this processor, boosting performance for calculation-heavy applications.