There are two other things restricting NX from porting current generation games.
First is RAM, PS4 has 5GB for a single game, what about NX? Second, due to reasonable power consumption CPU of NX may consume 5W at most, Let's say 1.2 GHz of quad-core A57. How much performance difference compared with Jaguar CPU?
Given Polygon pointed out Shield Doom BFG, while 1080/60, is running at significantly reduced graphical quality to the PS3/360 version, it might be better served asking how well NX (assuming Tegra X1) can run last gen ports...
According to Anandtech Tegra X1 has 25.6 GB memory bandwidth (LPDDR4 on 64 bit bus). I have no idea if that's the same configuration as in NX, but without EDRAM it would be at a significant effective bandwidth deficit to PS3/360. PS3 with it's dual buses.
Of course, I assume X1's compression tech is much greater...but it bears thinking this may be yet another Nintendo "sidegrade". Although, realistically, it should outperform PS3/360 clearly for a change.
It does show Zelda NX probably isn't killing the Wii U version, and makes sense why there's an NX version bandied about rather than a whole new game or something.
Assuming it isn't neutered for handheld power savings? The another option being to run the same games as a handheld with reduced graphical quality versus when docked.
The reason for this is because of the limited amount of data that can be stored on the cartridge.
A 32 GB cart is a lot isn't it? It actually seems like almost overkill for this amount of power, if anything. It's approaching Blu Ray size.
Regardless, it is nice as mentioned on GAF seeing Nintendo have a modern architecture for a change.