The Xbox 360 technical specifications describe the various components of the Xbox 360 video game console. The console features a port on the top when vertical (left side when horizontal) to which a custom-housed hard disk drive unit can be attached in sizes of either 20, 60, 120, 250, 320, 500 GB; and as of April 2015 all 2.5" SATA Hard Drives up to 2 TB, the user can use the format option from system settings to utilize the new HDD. Inside, the Xbox 360 uses the triple-core IBM designed Xenon as its CPU, with each core capable of simultaneously processing two threads, and can therefore operate on up to six threads at once. Graphics processing is handled by the ATI Xenos, which has 10 MB of eDRAM. Its main memory pool is 512 MB in size.