• What
    is this?
    You've landed on the AMD Portal on AnandTech. This section is sponsored by AMD. It features a collection of all of our independent AMD content, as well as Tweets & News from AMD directly. AMD will also be running a couple of huge giveaways here so check back for those.
    PRESENTED BY

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....

Fusion GPU Takes on Gaming AMD’s Llano Platform: Contending for your Mobile Dollar
POST A COMMENT

177 Comments

View All Comments

  • JarredWalton - Tuesday, June 14, 2011 - link

    The only way to make sure that Intel's current processors aren't at the top of most charts is to leave them out, particularly on notebooks. If we only look at IGP/fGPU, AMD comes out on top of graphics charts, but is that fair to NVIDIA's Optimus technology that allows dynamic switching between IGP and dGPU in a fraction of a second? The overall tone of this article (apart from the CrossFire section) is positive, but still people look at the charts and freak out because we didn't manipulate data to make Llano look even better. It's not bad, but it's certainly not without flaws. Reply
  • kevith - Tuesday, June 14, 2011 - link

    Oh too bad.

    I would like to use a laptop for music production with Nuendo and Win 7.

    It actually reqires a little more graphics-musclle than you might think to run an app like Nuendo.

    And,up to now, it has not been possible to get both a powerful CPU and GPU in the same machine for the money I have.

    So now the fGPU is powerful enough, that's great. But it seems, that the CPU-part of these APU's are too weak.

    Øv...
    Reply
  • krumme - Tuesday, June 14, 2011 - link

    Øhhh

    Just make sure your computer have 1Gb ram and win xp sp2, Nuendo even runs on single core 2Ghz whatever old shit.
    I would save the money and buy a e350.
    Heck you could even buy an Atom 510, acording to Anandtech, its just as fast as e350 for the cpu side.

    When i think about it. Just do that.
    Reply
  • ET - Tuesday, June 14, 2011 - link

    As madseven7 commented correctly, this isn't the fastest Llano CPU. There are 45W parts which perform better. They will have less battery life, but a significant increase in core speed. If you're interested in Llano you might want to wait until they get reviewed. Reply
  • JarredWalton - Tuesday, June 14, 2011 - link

    I suspect the 45W Llano parts will only have less battery life if you're specifically doing CPU/GPU intensive tasks. At idle, SNB and Llano should both bottom out at similar levels. For example, if you have a 2630QM and a 2820QM doing nothing, they both run at a very low clock and voltage. We'll test any other Llano chips we can get and report our findings, but other factors (BIOS and firmware optimizations) will generally be more important than whether the TDP is 35W or 45W, at least for our particular battery life tests. Reply
  • Shadowmaster625 - Tuesday, June 14, 2011 - link

    I dont get the Cinebench single threaded results. An N660 is about the same as a desktop X2 250/255 on that benchmark. Yet this A83500M scores only 61% of what an X2 250 does. That would seem to indicate that it is only running at 1.8GHz during that single threaded test. Why so low with 3 idle cores? It should be running at 2.5GHz and scoring 2500, or just neck and neck with a P520. Turbo is clearly not working anywhere near as well as it should be. Reply
  • krumme - Tuesday, June 14, 2011 - link

    Well this is AMD business at work. They are in a constant learning process and have been for the last 40 years.

    Next time they might consider the following:

    1. Dont send some half baked prototypes to the reviewers. Wait fx. 3 more weeks. This is just old Jerry Sanders style.

    2. Consider not sending stuff to Anandtech. As anandtech lives from backlinking also, the site needs the new product. And AMD, - and for the sake of the consumers right decisions, can live without 3 similar i7 plus high end discrete gfx, at 1.200 usd at the top of each chart. If AMD dont understand they have other interest than Anandtech - its business for all - they cannot serve their own interest. And its about time they start to earn their own money. They are competing against Otellini not some stupid schoolboy.
    Reply
  • JarredWalton - Tuesday, June 14, 2011 - link

    Thanks, krumme; always a helpful response. Lenovo has taken this to heart, I'm sure you'll be happy to know, and is not sending any review samples our way. Amazingly, we're still able to survive. And FWIW, if AMD hadn't sent us anything, we'd have had more content earlier through other sources. The only way they can get us to abide by NDAs is by actually working with us. Reply
  • krumme - Tuesday, June 14, 2011 - link

    Well thank you Jarred. That was an helpfull answer! that explains a lot.

    I hope AMD gives you attention and work with you in the future, its in all your readers interest.

    That means AMD giving you priority, broad access to the right people and more time to do the reviews.
    Reply
  • JarredWalton - Tuesday, June 14, 2011 - link

    This is something I discussed with AMD numerous times, and it's one of the reasons we want a utility that will show us true CPU clock speeds in real time. Unfortunately, they don't have anything they're willing to share with us right now. They said they have test units where they can monitor this stuff, but it requires special BIOS hooks and those are not present in our preview samples. In theory, Turbo Core should allow the single-threaded Cinebench result to run up to 60% faster than non-Turbo. Of course, we can't even disable Turbo Core either, so we don't know how much TC is actually helping.

    P920 is clocked 6.7% higher than A8-3500M, but 3500M has twice the L2 cache and some other enhancements. With 3500M coming in 17% faster than P920, that would suggest that 3500M averages around 1900MHz, but that could mean it runs at 2.4GHz for a bit and then 1.5GHz for a bit, or somewhere in between.

    Given the way AMD does Turbo Core (monitoring instruction workloads and their relative power requirements), I think that at least right now, it's not being as aggressive as Intel's Turbo Boost. It feels more like Bloomfield and Arrandale turbo, where you got an extra 2-4 bins, rather than Sandy Bridge where you can get an extra 5-10 bins. Hopefully we'll see refinements with Turbo Core over the coming months and years.
    Reply

Log in

Don't have an account? Sign up now