AMD Mantle: A Graphics API Tested In Depth

Features
By Don Woligroski
published

AMD's Mantle is available to users of certain Radeon cards, as are the first few titles with corresponding API support. We gathered up a number of CPUs and graphics boards, fired up Battlefield 4 and Thief, and set off on a benchmarking odyssey.

Battlefield 4: RAM Issues And Driver Updates

As mentioned, we let AMD know about our Mantle issues under Battlefield 4, and was told that the game currently suffers from an issue that results in lower performance on cards with less than 4 GB of memory. In order to test this issue, we were sent an MSI Radeon R9 270X with 4 GB of GDDR5. Does the extra memory alleviate our observed problem?

While we don't see the performance penalty that Mantle caused previously, there's no perceptible advantage, either.

Once again, the frame time variance is exceptionally low on average, and the occasional spikes make little difference.

For now, it appears that on-board memory isn't the only limiting factor. At least in Battlefield 4, Mantle demonstrates an advantage over DirectX on high-end cards with 4 GB of memory. The extra GDDR5 doesn't appear to help a Radeon R9 270X under the API.

Battlefield 4 (June 3 Update) And Catalyst 14.6 Beta Release Candidate 2

This is one of the most benchmark-intensive articles I've ever written, involving multiple graphics cards tested across multiple platforms. I began the project back when Catalyst 14.4 Beta was the newest driver available, but used Catalyst 14.3 Beta because there were instances of the 14.4 driver penalizing performance.

Once testing was complete, I spent a lot of time doing additional research. I discussed the numbers with AMD, which led to 4 GB corner case benchmarking. I did more homework on APIs, and Chris Angelini spent some time with AMD's Richard Huddy in Bakersfield. To make a long story short, enough time passed that Battlefield 4 received an update on June 3rd, and AMD released its Catalyst 14.6 Beta driver.

I needed to make sure that my Mantle-based performance data was still relevant, so I ran a few tests with the latest updates and found that, in Battlefield 4, performance under Mantle improved on video cards with less than 4 GB of memory. The bad news is that, while the gap gets smaller, AMD's API is still a tad slower with a less consistent frame rate than DirectX 11. Even though the gap is much closer, Mantle doesn't offer an advantage in anything less than a Radeon R9 290.

The bottom line is that Radeon cards with less than 4 GB of memory still do not benefit from a performance advantage in Battlefield 4 under Mantle. But with the newest driver and game patch, that hit is smaller than our numbers with the 14.3 Beta package. Its an encouraging development, which speaks to the work AMD and DICE are putting into the API. But it also shows us how much effort is required. We'd hope that Battlefield 4 would run faster under Mantle, regardless of the card installed and its on-board graphics memory capacity.

Don Woligroski
107 Comments Comment from the forums
  • damric
    Wow, Don. This is a good read. You must have plagiarized it from some somewhere :D


    Nice, Damric. nice. :)
    Reply
  • Amdlova
    memory problems... so my 260x with 1gb will sufferrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
    Reply
  • Memnarchon
    Mantle is not glide. 3DFX had 85% of the GPU share when they had glide so it was easier for developers to use the glide (AMD has 35% right now).
    But Mantle did something really good for gamers. Till now Microsoft with no competition didn't gave too much attention in performance optimising the DirectX. They gave Microsoft a reason to improve DirectX (so they will bring DX12) in the way mantle works. This benefits all the gamers.
    Unfortunately I have a feeling that Microsoft will give DirectX12 only with Windows9 (due to kernel limitations at their pockets).
    If this will be true then Mantle might have more life than most users expected to (since it wil take time for windows 9 to rule the market share)...
    Reply
  • ZolaIII
    Next Open GL specification is almost redy & will be announced next month in (ironically) Vancouver Canada. Naturally it will be available on all platforms (that want to integrate OGL) & it will be addressing lover overheads. As gaming market is getting more fragmented it's getting natural to develop for api that can run on all platforms.
    Reply
  • tomfreak
    Is the battlefield 4 tested in multi-player?


    It was tested in single player, as its easier to get consistent results. We're trying to eliminate variables except the graphics engine as much as possible.
    Reply
  • chaosmassive
    "AMD Mantle: AMD's PhysX "

    please do a research what is Mantle before post
    it seems you don't understand what are you writing about.


    I think the problem may be that you don't understand the context of the answer, which does not equate Mantle with PhysX on a technical level.

    We equate Mantle with PhysX in the sense that it's a value-add that assists in a limited number of games. Its not a universal advantage.
    Reply
  • abundantcores
    User testing around the Internet shows Intel are at least as fast in Mantle as AMD CPUs.

    Its obvious there is something very wrong with your testing.


    Actually, nobody on the internet has really tested anything but Radeon R9 290s when it comes to Mantle. Instead of assuming it always works in every situation like everyone else, we actually tested it, not only with the 290, but with a wide range of CPUs and GPUs. We did this with feedback from AMD.

    Mantle is not the perfect, slick API that people assume it is. AMD stresses that its considered a beta and is not yet a final product.

    I believe that our test results are quite accurate. The problem is that the API, something the developer considers unfinished at this point, probably still needs work and has room to grow. And I'm sure it will get better over time.

    But pretending it works 100% perfectly doesn't help anyone. That's not even something that AMD would try to say at this time as it has obvious issues. They are working on it. But there is a value to in-depth testing and to sharing the inconsistencies.
    i7 with 4 cores and 8 threads right here http://forums.overclockers.co.uk/showthread.php?p=26614553#post26614553

    Using your settings.

    Min 62 FPS
    Max 82 FPS

    here is one with a 4770K @ 4.5Ghz

    Avenged7Fold: 290X @ 1300/1604, 4770K @ 4.5Ghz - Mantle FPS: Min 71.8 / Avr 88.5. http://forums.overclockers.co.uk/showpost.php?p=26380265&postcount=291

    That ^^^ is actually on the highest possible settings.

    I know a lot of people using i7's with mantle, in Thief and BF4, some with CF 290's, they all report FPS gains with Mantle over DX, especially when in CF. in BF4 averaging 170 FPS with 120 FPS minimums. over 50% higher than they do in DX.

    I don't know where you have gone wrong. but everyone on our forum is utterly confused by your i7 results.

    http://forums.overclockers.co.uk/showthread.php?t=18611853
    Reply
  • ta152h
    As a programmer of 30 years, that's arguably the worst description of an API I have heard.

    An API is a set of commands, with required parameters, a software package presents to another application that wishes to use its services. It's essentially the language to use the services it provides.

    Mantle isn't just an API. It's an abstraction layer that makes it unnecessary for the developer to write directly to the hardware, which is tedious, time-consuming and extremely difficult to do on a large product. The API is what Mantle accepts to tell it what to do, and what the programmer must learn to use it, but it is NOT all Mantle is. It's just how to talk to it.

    A pure API would be something someone demented would write, because it would mean you could issue commands to do nothing. I'm guessing Apple is patenting this technology now.


    I'm sorry you feel that way. I don't agree as I feel it's a useful high-level primer for folks who haven't been programming for 30 years, but you're certainly entitled to your opinion. :)
    Reply
  • elbert
    On page 4 its clear mantle doesn't work well with Intel's Hyper-Threading but what about Intel's 6 core CPU's? Does mantle give an Intel 6 core a bigger advantage in games that dx? I wouldn't throw mantle under the bus just due to its unoptimized for Hyper-Threading. Please add an Intel's 6 core to these tests.
    Reply
  • SteelCity1981
    I can see intel supporting mantle in its future gpu hardware. I mean just recently intel asked amd for its mantles api specs. So intel using mantle in the future is much more plausible then Nvidia using mantle.
    Reply