The GeForce GTX 990M is believed to be based on the NVIDIA GM204 "Maxwell" architecture, similar to the GeForce GTX 980 desktop card.
The card will allegedly have a TDP around 100 to 185+W, so notebook manufacturers will need to come out with an impressive cooling system on their notebooks for optimum performance. Due to the high TDP, the chip will reportedly be soldered onto the motherboard and not be offered as a MXM solution.If the rumors are true, this chip may offer performance close to that of a GeForce GTX 980M in SLI! Unfortunately, pricing is expected to be roughly twice as high as that of the GTX 980M.