Nvidia has finally brought its next-generation Kepler architecture to the top of its notebook GPU lineup, with the launch of the Nvidia GeForce GTX 680M. The new chip shares some similarities with the desktop GTX 670, offering 1,344 CUDA cores and a 256-bit memory bus. Clock speeds will vary by system design, but maximum core frequency cited by Nvidia is 720MHz, while memory bandwidth is rated at 115GB/s.

In terms of performance, Nvidia's internal benchmarks show the GTX 680M is up to 80% faster than its GTX 675M/580M predecessor, and will be able to run many graphics-heavy games at 40FPS to 120FPS with high detail settings. For example, titles such as Battlefield 3, Dirt 3, Skyrim and Deus Ex: Human Revolution are all able to run at 60FPS or more with max detail settings in a 1920 x 1080 resolution.

The GTX 680M will make its way into Alienware M17x and M18x gaming laptops shortly, as well as the MSI GT70 and gaming laptops from Clevo channel partners such as Maingear and Origin.

Like other members of the GeForce 600M family it supports Nvidia's Optimus technology, which optimizes battery life by powering the GPU only when it's needed, Verde notebook drivers for performance and stability updates, PhysX, optional 3D Vision and 3DTV Play, and SLI configs for a performance boost.

As it stands, the GeForce 600M lineup features a die shrink and a couple of rebrands as we've become accustomed in the past, but there is a fair bit of Kepler across the board as well. Here's how it looks:

  GPU CUDA Cores GPU Clock Memory bus (bits) Memory Memory
GeForce GTX 680M 28nm GF104 1344 720MHz 256 up to 4GB GDDR5 115.2GB/s
GeForce GTX 675M 40nm GF114 384 620MHz 256 up to 2GB GDDR5 96GB/s
GeForce GTX 670M 40nm GF114 336 598MHZ 192 up to 3GB GDDR5 72GB/s
GeForce GTX 660M 28nm GK107 384 835MHZ 128 up to 2GB GDDR5 64GB/s
GeForce GT 650M 28nm GK107 384 735/850MHz 128 up to 2GB DDR3
or GDDR5
up to 64GB/s
GeForce GT 640M 28nm GK107 384 up to 625MHZ 128 up to 2GB DDR3
or GDDR5
up to 64GB/s
GeForce GT 640M LE 40nm GF108 or 
28nm GK107
96 or up
to 384
762MHz or up to 500MHz 128 up to 2GB DDR3
or GDDR5
up to 50.2 or 28.8GB/s
GeForce GT 635M 40nm GF116 144/96 Up to 675/753MHz up to 192 up to 2GB GDDR5 up to 43.2GB/s
GeForce GT 630M 28nm/40nm GF108 144/96 up to 525/672MHz 128 up to 2GB GDDR5 up to 28.8GB/s
GeForce GT 620M 28nm GF108 96 up to 625MHZ up to 128 up to 1GB DDR3 up to 28.8GB/s
GeForce 610M 40nm GF119 48 up to 900MHZ 64 DDR3 Up to 14.4GB/s