Is AMD's Mantle really worth it?

Intel Gamer: Intel Core i5-4570

The Intel processor ironically seems to benefit the most from the introduction of the Mantle API. While the AMD processors get impressive performance boosts – therefore bringing them closer to the gaming pace of the Intel chips – those blue CPUs also get a lift.

This Core i5 is actually able to squeeze more performance from its partnership with the otherwise struggling HD 7870, and gets a hefty boost from the R9 290 pairing as well. The interesting thing for Intel is that it doesn't suffer from the same collapse in minimum frame rates that befalls AMD processors. We put the shaky performance down to the immature beta API still not being quite finished. While the i5's frame rates get smoother across the board, AMD frame rates stutter more and more.

In general, we don't see as much of a percentage performance gain as we do with the AMD processors, but that's mostly because the DirectX starting point has far higher average frame rates anyway. Where game engines are CPU bound, Intel chips outperform the competition.

When you bring Mantle into play, the gap in performance may often be cut but the Intel chips still come out on top. Nonetheless, where games are mostly GPU bound, Mantle ensures that the AMD processors aren't left behind. That is highlighted best in the 4K BF4 tests. There is almost no boost on Ultra, but on High both AMD and Intel saw the same boost and hit the same average frame rates.

Performance on the AMD Radeon R9 290 - 1080p (FPS, higher is better)

  • Battlefield 4 - Mantle (min/avg): 55/82
  • Battlefield 4 - DirectX (min/avg): 45/72
  • StarSwarm - Mantle: 57
  • StarSwarm - DirectX: 38

Performance on the AMD Radeon HD 7870 - 1080p (FPS, higher is better)

  • Battlefield 4 Ultra - Mantle (min/avg): 19/58
  • Battlefield 4 Ultra - DirectX (min/avg): 31/51
  • StarSwarm - Mantle: 42
  • StarSwarm - DirectX: 32

Conclusion: Good news for Intel

Unfortunately for all you AMD CPU fans, Mantle isn't the magic bullet to give its processors a boost over the Intel-shaped competition. While Mantle does allow the FX processors to get a lot closer to the performance of Intel CPUs, 4th-gen Core chips get a boost of their own. The new API isn't going to change Intel's desktop dominance of the gaming market.

After looking at the performance boosts that Mantle API offers the processor landscape, we think we might have more of a handle on AMD's strategy. When it was announced that AMD wasn't looking to roll out the Steamroller core update to its FX line of CPUs and was limiting it to the Kaveri APUs, we questioned that decision. Now it seems clearer: AMD has essentially given up on the straight CPU. That's not as defeatist a line as it might at first sound.

Given that most gamers would rather have an Intel CPU at the heart of their rigs, has AMD decided that it needs to focus on making sure that those gamers are pairing their Intel silicon with an AMD card? Forget trying to get them to buy a weaker FX chip, let's just stop them buying an Nvidia GPU to go with their Intel CPU. With Mantle and an Intel CPU, you get an increase in average frame rates as well as in minimum frame rates.

That means your Mantle enabled game is not only quicker on an Intel CPU/AMD GPU PC, but smoother too. It's the same situation in the Battlefield 4 test as it is in the Star Swarm benchmark. Star Swarm proves that when an engine is coded with Mantle in mind from its early development, the performance boost is more consistent across different platforms.

In Battlefield 4, the HD 7870 is a nightmare for the AMD setups, while in Star Swarm both R9 290 and HD 7870 get the same sort of backing. This is all good news for us PC gamers, especially those of us who are already sitting on an AMD GCN-based card. It's true that at present, the Hawaii cards get the best of Mantle, but in the future, the whole stack should get a decent boost from Mantle compatible games – and that's got to be a little worrisome for Nvidia.