Some benchmarks of NVIDIA's new GeForce GTX 860M were leaked online. This new chip seems to have an identical setup to the Maxwell-based GeForce GTX 750 Ti, it has 640 CUDA cores, 40 TMUs, 16 ROPs, a 128-bit memory bus, a 540MHz core clockspeed and 2GB GDDR5 memory clocked at 5000MHz.
In 3DMark11 the card achieved a score almost twice that of the GeForce GTX 660M:
The chip’s 3D Mark 11 performance score clocked in at P5339 while its extreme score came in at X1662. In comparison the GTX 660M has a performance score of P2563 and an extreme score of X774.