A family of 64-bit x86 CPUs with up to eight cores from Intel that were introduced in 2008 as the successor to Core 2. The Core i7 chips are the high-end CPUs in the Core "i" line, although Intel's Xeon chips, which use the same architecture, have more enterprise features (see Xeon). The first models included a graphics processing unit (GPU) in the same chip package as the CPU; however, 2nd Generation Core models, introduced in 2011, integrate a GPU on the same die as the CPU. See GPU, Nehalem and Sandy Bridge. Enhanced Memory Control Supporting three channels of DDR3 memory, the Core i7 contains its own memory controller that runs with a separate clock in the "uncore" area (a part of the chip that is not executing program instructions). QuickPath and Turbo Boost A major feature is the QuickPath system interconnect, which is a high-speed, packet-oriented, point-to-point pathway between the CPU cores and memory and between the cores and I/O hub. Depending on the multiprocessor capability supported by the chip model, an integrated crossbar router between the cores may be included. The i7 line also introduced Turbo Boost, also available in some i5 models, which allows the speed of CPU cores to be adjusted (see Turbo Boost). See Core i5 and Core i3.