The Intel Xeon L5639 was a server/workstation processor with 6 cores, launched in February 2011. It is part of the Xeon lineup, using the Westmere-EP architecture with Socket 1366. Thanks to Intel Hyper-Threading the core-count is effectively doubled, to 12 threads. To further increase overall system performance, up to two Xeon L5639 CPUs can work together in a multi-processor (SMP) configuration. Xeon L5639 has 12 MB of L3 cache and operates at 2.133 GHz by default, but can boost up to 2.667 GHz, depending on the workload. Intel is making the Xeon L5639 on a 32 nm production node using 1,170 million transistors. The multiplier is locked on Xeon L5639, which limits its overclocking potential.
With a TDP of 60 W, the Xeon L5639 consumes typical power levels for a modern PC. Intel's processor supports DDR3 memory with a triple-channel interface. The highest officially supported memory speed is 1333 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 system, Xeon L5639 uses a PCI-Express Gen 2 connection. This processor lacks integrated graphics, you might need a graphics card.
Hardware virtualization is available on the Xeon L5639, which greatly improves virtual machine performance. Additionally, IOMMU virtualization (PCI passthrough) is supported, so that guest virtual machines may directly use host hardware.