We were originally clued in to the then-unannounced Nvidia GeForce GTX680M mobile gaming GPU when Origin PC announced that its EOS15-S and EOS17-S laptops would include it. After reaching out to Nvidia for more details, the GPU maker officially announced this chip, and in terms of mobile gaming, what a chip it is. The GTX 680M is the newest mobile chipset from Nvidia using the Kepler architecture. It's designed to bring desktop-class performance to laptops, and theoretically achieves that goal by combining the power-saving multi-threaded processing, a 28nm manufacturing process, and even Nvidia's GPU Boost feature, which increases the GPU speed if temperatures allow.
The GTX 680M core is manufactured at 28nm and includes a staggering 1344 cores at 720MHz. The GPU supports up to 4GB of GDDR5 RAM with an effective clock rate of 3.6GHz running on a 256bit memory bus, and has a bandwidth of 115.2GB/s. This represents a 20 percent increase in memory bandwidth and a possible 80 percent overall improvement over the GTX 580M according to HotHardware. By way of comparison, the 40nm Fermi-based GTX 675M is next in line using 384 cores running at 620MHz, and then the newer Kepler-based GTX 660M running 684 cores at 835MHz. As mentioned before, Origin PC's laptops can be configured with the chip, and the Alienware M17x and the MSI GT70 will also get treated to Nvidia's fastest mobile gaming GPU.