Both GPUs will be positioned as slightly more powerful than their existing GTX 970M and GTX 980M counterparts with increased CUDA cores, texture units, and clock speed while retaining the same TDP. In addition to the aforementioned, the 970MX has 56 ROPs vs 48 in the 970M while the 980M and 980MX have the same 64 ROPs.
WCCFTech created a table which shows the differences between the new GPUs and existing ones:
Model GeForce GTX 980 Laptop Version GeForce GTX 980MX GeForce GTX 980M GeForce GTX 970MX GeForce GTX 970M GeForce GTX 965M GeForce GTX 960M Architecture Maxwell Maxwell Maxwell Maxwell Maxwell Maxwell Maxwell GPU GM204 GM204 GM204 GM204 GM204 GM204 GM107 CUDA cores 2048 1664 1536 1408 1280 1024 640 Texture Units 128 104 96 88 80 64 40 Raster Devices 64 64 64 56 48 32 16 Clock Speed 1218 MHz 1048 MHz 1038 MHz 941 MHz 924 MHz 950 MHz 1097 MHz Memory Bus 256-bit 256-bit 256-bit 192-bit 192-bit 128-bit 128-bit Amount of memory 8 GB GDDR5 8/4 GB GDDR5 8/4 GB GDDR5 3/6 GB GDDR5 3/6 GB GDDR5 4 GB GDDR5 4 GB GDDR5 Memory Frequency 7008 MHz 5000 MHz 5000 MHz 5000 MHz 5000 MHz 5000 MHz 5000 MHz Memory Bandwidth 224 GB/s 160 GB / s 160 GB / s 120 GB / s 120 GB / s 80 GB/s 80 GB/s TDP ~150W 125W 125W 100W 100W 90W 75W Table Source: WCCFTech
There's no word on what the price will be for these new cards or what notebooks will feature them but if I had to guess, I'd say the usual suspects like Alienware, Clevo, MSI and Asus will be among the first to have these ready.