Originally Posted by PureBlackFire
this. nvapi is still nvidia's api like mantle is amd's. the big and important difference is that console gaming (the main focus of all the gaming dollars and attention) is running 100% on amd graphics hardware so amd's api is going to have widespread adoption on pc and far more potential to affect the performance of amd graphics cards in games that use it. amd has all the leverage, they just need to stop dropping the ball. on topic, battlebox seems like an idea that's better in the concept stage, but looses it's appeal in the end. at the end of the day it's still another expensive custom build that people will hesitate to buy.
To this day AMD didn't have such low APIs and we haven't seen games that ran significantly better on Nvidia to this date (if you except AMD frame latency and PhysX titles), so if Mantle lives up to the numbers (even approx.) it should give far better performance than NVAPI.
Also of course the closer you get to hardware the harder it is to code (well maybe much less if you are accustomed to the arch specificities?) that's for sure.