The Battlefield 4 patch with Mantle support was just released. Unfortunately, AMD does not have a driver ready today. As explained in our previous Mantle article, only in CPU limited situations you will gain performance with Mantle. DICE just released some numbers as well, these are their own internal tests showing performance differences in-between DirectX 11.1 and Mantle.
DICE created three setups from low to high-end. Now I do have to make this statement; all setups seem to be CPU limited (which will benefit Mantle) which I find to be a little akward. You could say that this respect the DICE results are somewhat flawed and have been catered to make Mantle look good.
Entry-level gaming, mainstream gaming, and enthusiast gaming.
Entry-level Gaming - AMD A10-7850K APU, integrated Radeon R7 200 series GPU (512 stream processors, 720 MHz GPU clock) tested at 1280 x 720 pixels resolution. With Mantle, the game yielded about 14 percent higher frame-rates.
Mainstream level gaming - AMD FX-8350 with a Radeon HD 7970 run at 1920 x 1080 pixels resolution with 1x MSAA and "Ultra" preset. Here you'll notice a 26 percent higher frame-rates. However, AMD FX cores offer half the performance per core opposed to Intel Core series processors. Meaning that despite the good results, these tests still have been performed under a very CPU limited situation, and thus that explains the performance boost.
Enthusiast level gaming - An Intel Core i7-3960X CPU with two Radeon R9 290X (CrossFire) graphics. Now here again I find the choice in components versus game resolution weird, as it seems DICE created a CPU limited situation (two cards in Crossfire) at a relatively low 1920 x 1080 resolution, the game is set at "Ultra" preset with 4x MSAA. Here it made all the difference with an 58 percent increase in framerates.
Personally I feel that you do not invest 900 EUR worth of GPUs and 1000 EUR on a CPU and then will game at 1080P. The test would have been far more reliable if it was done at 2560x1440 with one card or Ultra HD with two cards. Let us know what you think in the forums.