The AMD Athlon II X4 638 was a desktop processor with 4 cores, launched in February 2012. It is part of the Athlon II X4 lineup, using the Llano architecture with Socket FM1. Athlon II X4 638 has 1 MB of L2 cache per core and operates at 2.7 GHz. AMD is making the Athlon II X4 638 on a 32 nm production node using 1,178 million transistors. The silicon die of the chip is not fabricated at AMD, but at the foundry of GlobalFoundries. The multiplier is locked on Athlon II X4 638, which limits its overclocking potential.
With a TDP of 65 W, the Athlon II X4 638 consumes typical power levels for a modern PC. AMD's processor supports DDR3 memory with a dual-channel interface. The highest officially supported memory speed is 1866 MT/s, but with overclocking (and the right memory modules) you can go even higher. For communication with other components in the computer, Athlon II X4 638 uses a PCI-Express Gen 2 connection. This processor does not have integrated graphics, you will need a separate graphics card.
Hardware virtualization is available on the Athlon II X4 638, which greatly improves virtual machine performance.