High Detail Gaming and Asymmetrical CrossFire Misfire

Update, 8/10/2011: Just to let you know, AMD managed to get me a new BIOS to address some of the rendering issues I experienced with CrossFire. As you'll read below, I had problems in several titles, and I still take exception with the "DX10/11 only" approach. I can name dozens of good games out there that are DX9-only that released in the past year. Anyway, the updated BIOS has at least addressed the rendering errors I noticed, so retail Asymmetrical CrossFire laptops should do better. With that disclaimer out of the way, here's my initial experience from two months back.

So far, the story for Llano and gaming has been quite good. The notebook we received comes with the 6620G fGPU along with a 6630M dGPU, though, and AMD has enabled Asymmetrical CrossFire...sort of. The results for ACF in 3DMarks were interesting if only academic, so now we're going to look at how Llano performs with ACF enabled and running at our High detail settings (using an external LCD).

Just a warning before we get to the charts: this is preproduction hardware, and AMD informed us (post-review) that they stopped worrying about fixing BIOS issues on this particular laptop because it isn't going to see production. AMD sent us an updated driver late last week that was supposed to address some of the CrossFire issues, but in our experience it didn’t help and actually hurt in a few titles. Given that the heart of the problem is in the current BIOS, that might also explain why Turbo Core doesn't seem to be working as well as we would expect.

AMD also notes that the current ACF implementation only works on DX10/11 games, and at present that's their plan going forwards as the majority of software vendors state they will be moving to DX10/11. While the future might be a DX10/11 world, the fact is that many recent titles are still DX9 only. Even at our "High" settings, five of our ten titles are tested in DX9 mode (DiRT 2, L4D2, Mafia II, Mass Effect 2, and StarCraft II—lots of twos in there, I know!), so they shouldn't show any improvement...and they don't. Of those five titles, four don't have any support for DX10/11 (DiRT 2 being the exception), and even very recent, high-profile games are still shipping in DX9 form (e.g. Crysis 2, though a DX11 patch is still in the works).  Not showing an improvement is one thing, but as we'll see in a moment, enabling CrossFire mode actually reduces performance by 10-15% relative to the dGPU. That's the bad news. The good news is that the other half of the games show moderate performance increases over the dGPU.

If that doesn't make the situation patently clear, CrossFire on our test unit is largely not in what we consider a working state. With that out of the way, here are the results we did managed to cobble together:

Battlefield: Bad Company 2

Civilization V

DiRT 2

Left 4 Dead 2

Mafia II

Mass Effect 2

Metro 2033

STALKER: Call of Pripyat

StarCraft II: Wings of Liberty

Total War: Shogun 2

Given this is preproduction hardware that won't see a store shelf, the above results are almost meaningless. If ACF can provide at least a 30% increase on average, like what we see in TWS2, it could be useful. If it can't do at least 30%, it seems like switchable graphics with an HD 6730M would be less problematic and provide better performance. The only takeaway we have right now is that ACF is largely not working on this particular unit. Shipping hardware and drivers should be better (they could hardly be worse), but let's just do a quick discussion of the results.

If we just look at games with DX10/11 enabled, the story isn't too bad. Not accounting for the rendering issues noted below, ACF is able to boost performance by an average of 24% over the dGPU at our High settings. We didn’t include the Low and Medium results for ACF on the previous page for what should be obvious reasons, but if the results at our High settings are less than stellar, Low and Medium settings are even less impressive. Trimming our list of titles to three games (we tested TWS2 and STALKER in DX9 mode at our Low and Medium settings), ACF manages to average a 1% performance increase over the dGPU at Low and a 14% increase at Medium, but Civ5 still had to contend with rendering errors and Metro 2033 showed reduced performance.

In terms of rendering quality, ACF is very buggy on the test system; the default BIOS settings initially resulted in corrupted output for most games and 3D apps, but even with the correct settings we still encountered plenty of rendering errors. Civilization V only had one GPU rendering everything properly while units were missing on the other GPU, so you’d get a flicker every other frame with units appearing/disappearing. At higher detail settings, the corruption was even more severe. STALKER: Call of Pripyat and Total War: Shogun 2 also had rendering errors/flickering at higher quality settings. Since we didn't enable DX10/11 until our High defaults, right when ACF is supposed to start helping is where we encountered rendering issues.

Just to be clear: none of this means that Asymmetrical CrossFire is a bad idea; it just needs a lot more work on the drivers and BIOS. If/when we get a retail notebook that includes Asymmetrical CrossFire support, we’ll be sure to revisit the topic. Why ACF isn’t supported in DX9 is still a looming question, and AMD’s drivers need a much better interface for managing switchable graphics profiles. A list of all supported games with a central location to change all the settings would be a huge step up from the current UI, and users need the ability to enable/disable CrossFire support on a per-game basis if AMD wants anyone to actually use ACF. We also hope AMD rethinks their “only for DX10/DX11 modes” stance; CrossFire has worked with numerous DX9 games in the past, and what we’d like to see is ACF with the same list of supported games as regular CrossFire. If nothing else, having ACF enabled shouldn't reduce performance in DX9 titles.

In summary: we don't know if ACF will really help that much. We tested Asymmetrical CrossFire on what is, at best, beta hardware and drivers, and it didn't work very well. We want it to work, and the potential is certainly there, but we'll need to wait for a better test platform. To be continued....

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  • JarredWalton - Tuesday, June 14, 2011 - link

    Civ5 and TWS2 are both tested with the latest drivers. The K53E was also tested with drivers that are at most a couple months old. Intel current lists the latest laptop drivers as from 4/13/2011, which is what I'm running on the Intel units right now. If there are some newer drivers that I'm missing out on, let me know and I'll go try them. Reply
  • duploxxx - Tuesday, June 14, 2011 - link

    Nice review, it seems like there is a lot of work on CF.

    Actually I reviewed the Liano already months ago, I mentioned in the last mobile reviews that it will be better performing then the Toshiba with the P920 with really good battery performance. So it is a win -win for the budget line anyhow. Top line remains intel for the CPU power.

    Regarding the quote:
    Now if you want to have your cake and eat it too, the APU to wait for would be Trinity. Due out somewhere in the 2012 - 2013 timeframe, combine a Bulldozer derived architecture with AMD's next-generation GPU architecture and you've got Trinity.

    Trinity will not only be an improved GPU it also has the BD core inthere which will offer much more punch. THe reason LIano is late is because of the 32NM process. It could have been released much sooner. Sure they took an outdated K10 and that is the main issue together with the not enough aggressive Turbo for single thread, they should have adapted this more aka BD.

    But assumin Trinity is a rather late 2012 project (by stating 2012-2013) you are way way off...
  • ET - Tuesday, June 14, 2011 - link

    Quote probably reflects an increase in pessimism due to recent events. Bulldozer is still not out, and AMD is said to have had a hard time getting clocks up. So sure, we're all hoping to see Trinity early in 2012, but anyone setting their expectations a little farther are less likely to be disappointed. Reply
  • duploxxx - Wednesday, June 15, 2011 - link

    didn't i mentioned it would be launch faster then expected?


    the delay of Zambezi BD has nothing to do with real architecture issues.....
  • ET - Wednesday, June 15, 2011 - link

    That's not the sites which posted on it, including Anandtech, said based on what AMD said (that is, that Bulldozer was not up to speed). Reply
  • Jamahl - Tuesday, June 14, 2011 - link

    Was that really needed? I mean...really? Who the hell would do that and for what reason? Reply
  • ET - Tuesday, June 14, 2011 - link

    I already got my E-350 laptop, but as Jarred says, Brazos just became less interesting. I'll be waiting to see what price point and performance the dual core Llano will have. What impressed me most was battery life, which is competitive with the E-350 laptop, and it'd be interesting to see how small and light Llano laptops will get.

    The other takeaway I have from this is that as usual I'm impressed at how far Intel has gone with its integrated graphics. Sure Llano gives it a good beating, but that's at the expense of a lot more die space. I imagine that Intel will continue to tweak its 3D cores and I can't wait to see how this race will develop.
  • Anosh - Tuesday, June 14, 2011 - link

    What happened to power consumption?!
    Some of us get laptops due to the optimization in the power department over similar desktop parts!
  • JarredWalton - Tuesday, June 14, 2011 - link

    Power = [Battery Capacity] / .98 [efficiency] / ([Battery life in minutes] / 60)

    So if you take the battery life charts, you can determine roughly what the total system power draw is using the above. Or you can look at the "Relative Battery Life" charts and get the same information as Minutes/Wh instead of converting into Watts.
  • jabber - Tuesday, June 14, 2011 - link

    In my work I get a lot of laptops to fix. If there is one game or genre that appears on 80% or more of them its......

    The Sims.

    I also get asked a lot "if I buy this laptop will it play The Sims?"

    Never ever been asked if a laptop will play Crysis or any of the games you use.

    Just saying.

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