It looks like NVIDIA is doing some last minute work to its GeForce GTX 965M product, codenamed "N16E-GR", allowing for some decent overclocking headroom and additional performance, adding roughly 15% to the previous "N16E-GS" product.
We don't know if the new GPU will be a more efficient revision of the GM204, or a full-blown GM206 part. It looks like we have a 15% performance improvement thanks to the increased clocks, with the Base clock said to be hitting 950MHz or so. NotebookCheck has run some prelimiary benchmarks, with the new GTX 965M clocking in at around 15% faster than the original chip.
In 3DMark 11, it scores around 8400 points, with a Base clock originally sitting at 924MHz, and now increased to 950MHz, while the Boost clock jumped from 1151MHz to 1175MHz or so. The GTX 965M will include a 128-bit memory bus allowing for 80GB/sec memory bandwidth, with 4GB of GDDR5. As for availability, we should expect sometime in Q1 2016, with the same price as the previous GTX 965M. The TDP should sit at around 50W, which is pretty good for mobile gaming, with HDMI 2.0 joining in on the fun.