The processor powering Microsoft's HoloLens augmented reality headset has been a mystery -- until now. During the annual Hot Chips conference in Cupertino, California, Microsoft revealed some juicy details about the secretive chip. PCWorld reports: "The HoloLens' HPU is a custom 28nm coprocessor designed by TSMC, The Register reports. The chip packs 24 Tensilica digital signal processor (DSP) cores. As opposed to more general-purpose CPU cores, DSPs are a specialized technology designed for rapidly processing data flowing in from the world -- a no doubt invaluable asset while rendering augmented reality environments in real time. Microsoft's HPU also contains roughly 65 million logic gates, 8MB of SDRAM, and 1GB of traditional DDR3 RAM. It draws less than 10W of power, and features PCIe and standard serial interfaces. The HPU's dedicated hardware is up to 200 times faster than performing the same calculations via software on the less-specialized 14nm Intel Cherry Trail CPU. Microsoft added custom instructions to the DSP cores that allow the HPU to churn through HoloLens-specific tasks even faster, The Register reports. The HPU can perform roughly 1 trillion calculations per second, and the data it passes to the CPU requires little additional processing."