Synthetics

As always we’ll also take a quick look at synthetic performance. Since Fiji is based on the same GCN 1.2 architecture as Tonga (R9 285), we are not expecting too much new here.

Synthetic: TessMark, Image Set 4, 64x Tessellation

First off we have tessellation performance. As we discussed in greater detail in our look at Fiji’s architecture, AMD has made some tessellation/geometry optimizations in GCN 1.2, and then went above and beyond that for Fiji. As a result tessellation performance on the R9 Fury X is even between than the R9 285 and the R9 290X, improving by about 33% in the case of TessMark. This is the best performing AMD product to date, besting even the R9 295X2. However AMD still won’t quite catch up to NVIDIA for the time being.

Synthetic: 3DMark Vantage Texel Fill

As for texture fillrates, the performance here is outstanding, though not unexpected. R9 Fury X has 256 texture units, the most of any single GPU card, and this increased texture fillrate is exactly in line with the theoretical predictions based on the increased number of texture units.

Synthetic: 3DMark Vantage Pixel Fill

Finally, the 3DMark Vantage pixel fillrate test is not surprising, but it is none the less a solid and important outcome for AMD. Thanks to their delta frame buffer compression technology, they see the same kind of massive pixel fillrate improvements here as we saw on the R9 285 last year, and NVIDIA’s Maxwell 2 series. At this point R9 Fury X’s ROPs are pushing more than 40 billion pixels per second, a better than 2x improvement over the R9 290X despite the identical ROP count, and an important reminder of the potential impact of the combination of compression and HBM’s very high memory bandwidth. AMD’s ROPs are reaching efficiency levels simply not attainable before.

Grand Theft Auto V Compute
Comments Locked

458 Comments

View All Comments

  • Navvie - Thursday, July 2, 2015 - link

    "Which is not say I’m looking" (paragraph 5, first line).

    Missing a "to" I think.
  • watzupken - Thursday, July 2, 2015 - link

    Brilliant review. Well worth the wait. Thanks Ryan.
  • Taracta - Thursday, July 2, 2015 - link

    ROPs, ROPs, ROPs! Hows can they ~ double everything else and keep the same amount of ROPs and expect to win?
  • Thatguy97 - Thursday, July 2, 2015 - link

    maybe something to do with cost or yield
  • tipoo - Thursday, July 2, 2015 - link

    They literally hit the size limits interposers can scale up to with this chip - so they can't make it any bigger to pack more transistors for more ROPs, until a die shrink. So they decided on a tradeoff, favouring other things than ROPs.
  • Kevin G - Thursday, July 2, 2015 - link

    They had a monster shader count and likely would be fine if they went to 3840 max to make room for more ROPs. 96 or 128 ROPs would have been impressive and really made this chip push lots of pixels. With HBM and the new delta color compression algorithm, there should be enough bandwidth to support these additional ROPs without bottle necking them.

    AMD also scaled the number of TMUs with the shaders but it likely wouldn't have hurt to have increased them by 50% too. Alternatively AMD could have redesigned the TMUs to have better 16 bit per channel texture support. Either of these changes would have put the texel throughput well beyond the GM200's theoretical throughput. I have a feeling that this is one of the bottlenecks that helps the GM200 pull ahead of Fiji.
  • tipoo - Friday, July 3, 2015 - link

    Not saying it was the best tradeoff - just explaining. They quite literally could not go bigger in this case.
  • testbug00 - Sunday, July 5, 2015 - link

    the performances scaling as resolution increase is better than Nvidia, implying the ROPs aren't the bottleneck...
  • chizow - Sunday, July 5, 2015 - link

    No, that implies the shaders are the bottleneck at higher resolutions while ROP/fillrate/geometry remained constant. While Nvidia's bottleneck at lower resolutions isn't shader bound but their higher ROP/fillrate allows them to realize this benefit in actual FPS, AMD's ROPs are saturated and simply can't produce more frames.
  • Ryan Smith - Thursday, July 2, 2015 - link

    Right now there's not a lot of evidence for R9 Fury X being ROP limited. The performance we're seeing does not have any tell-tale signs of being ROP-bound, only hints here and there that may be the ROPs, or could just as well be the front-end.

    While Hawaii was due for the update, I'm not so sure we need to jump up in ROPs again so soon.

Log in

Don't have an account? Sign up now