In recent years, the power difference between desktops and laptops graphics cards has been cut. In fact, in the presentation of the GTX 980M, Nvidia indicated the fact that it had a 80% power of the GTX 980 for desktop computers, while the GTX 970M was at 60% power the GTX 970.
While for some gamers that look for a new laptop this is unacceptable, they are still the lucky ones. From now on, you can find laptops that have the GTX 980 chip in portable size, while maintaining their consumption of 165 W, with the cooling problems that may entail.
So it depends on manufacturers to create cooling systems that are suitable for these notebooks, and the MSI GT72 with the GTX 980 option is a huge laptop with 17-inch screen and more than 5 cm in thickness. But yes, Nvidia promises that these chips will operate at the speeds of the desktop versions, and also allow the same overclock, in the range of 200 Hz.