The Intel Xeon X5660 was a server/workstation processor with 6 cores, launched in March 2010. 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 X5660 CPUs can link up in a multi-processor (SMP) configuration. Xeon X5660 has 12 MB of L3 cache and operates at 2.8 GHz by default, but can boost up to 3.2 GHz, depending on the workload. Intel is building the Xeon X5660 on a 32 nm production process using 1,170 million transistors. The multiplier is locked on Xeon X5660, which limits its overclocking capabilities.
With a TDP of 95 W, the Xeon X5660 consumes a good deal of power, so decent cooling is needed. Intel's processor supports DDR3 memory with a triple-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 machine, Xeon X5660 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 X5660, which greatly improves virtual machine performance.