Well Again GTX 780TI on top.
This isn't surprising at all. It's a well known fact that the 780Ti is about 30% faster than a 290x when we are mostly GPU limited. (they are claiming a single player map makes the CPU the bottleneck... they are mostly wrong. For that, they need to do multiplayer tests)
Nvidia didn't price the Ti at a higher MSRP just to price themselves out of the market, they did it because it's the faster card.
But then there is multiplayer BF4, which is what most people that actually play BF4 care about.
And if you've used mantle on multiplayer, you would know just how unbelievable the difference in performance can be.
I run a strobed 120hz Monitor, and both my avarage and minimum FPS are much, much higher now.
Anywhere from as low as (i'm guessing) 20% to as high as 100% on certain areas. Where i would avarage 50-70 FPS i now avarage anywhere from 70 to 100 FPS, sometimes even exceeding 120 FPS (playing with vsync off, no adaptive vsync on mantle, which is a shame)
And on maps like siege of Shanghai, the difference is just tremendous.
Under D3D there used to be areas where my FPS would dip as low as 39 FPS (rare, but it did happen) and under mantle the lowest my FPS ever gets is around 69.
The big gain here, are both the minimum framerates that are now much, much higher. And the fact that the framerates are much more consistent across the board now, MP now looks as smooth as the single player campaign did.
TL;DR: mantle is a game changer for BF4 multiplayer. I still have a hard time believing just how smooth it looks every time i join a 64 session.