Asymmetric CrossFire

Asymmetric CrossFire is supported by desktop Llano APUs. You can combine your A6 or A8 with a Radeon HD 6450, 6570 or 6670 and have both GPUs work in tandem. There are some limitations as we found - mainly asymmetric CF only works in DX10 or DX11 games. While DirectX 9 titles will still function, performance will be suboptimal as you'll soon see.

AMD Radeon Dual Graphics Branding
Discrete GPU 6550D 6530D
HD 6670 HD 6690D2 HD 6690D2
HD 6570 HD 6630D2 HD 6610D2
HD 6450 HD 6550D2 HD 6550D2

Getting asymmetric CrossFire working was a breeze. ASRock's BIOS was setup by default to allow for a secondary discrete GPU to function in dual-graphics mode, all I had to do was install a Radeon HD 6570. My monitor remained plugged into the motherboard and the driver handled the rest:

If you're running a DX10/DX11 game you can get positive scaling, however the gains vary. In Crysis we saw a 68% increase in performance over the APU alone, but only a 12% increase over the discrete GPU by itself:

Crysis: Warhead

HAWX showed us bigger gains on both sides. We saw a more than 2x improvement over the APU alone and a 32% increase over the Radeon HD 6570 by itself:

HAWX

Fire up a DX9 game (or a DX10/11 game in DX9 mode) however, and the results are disappointing. You actually get lower performance than if you had stuck with the discrete GPU alone:

Metro 2033

DiRT 2

Mass Effect 2

StarCraft II

GPU Performance Performance in Older Games
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  • zac05 - Thursday, June 30, 2011 - link

    was waitting for this reviw very badily......

    probabily amd llano desktop version is just a beafed up amd apu mobile version, it has a clear winnig point on its mobile platform ( added advantage of batterylife and graphics performance for relatively lower price than the intel counter part )

    but for desktop its a mixed review....i think the bulldozer family apu..which is the real desktop apu variant must come into picture, for a face to face comparison with the intel counter part ...phew we have to wait another 4-5 months for that i guess.

    a8-3850 would be good for casula gamers....else i3 will provide more performance and lower tdp for others
  • Musafir_86 - Thursday, June 30, 2011 - link

    Hi Anand,

    -Thank you for the nice review, but would you add image quality (IQ) comparison as well? From what I found around the internet, Intel HD 2000/3000 still lacking competitive/comparable quality of the rendered images. So, it would be better to show what's the actual IQ the user will see even when the frame rate (FPS) looks like it's playable.

    Thanks again.
  • ganeshts - Thursday, June 30, 2011 - link

    Yes, that is coming up in a separate review. Give me a couple of hours.
  • Musafir_86 - Thursday, June 30, 2011 - link

    -Wow, what a quick reply, thanks!

    -Hmm, Anand said you're covering HTPC scenarios, right? So would that mean video (output) quality only? Or that will include 3D games as well?

    Regards.
  • StormyParis - Thursday, June 30, 2011 - link

    Thanks. very much looking forward to that t, being gaming or video.
  • AnandThenMan - Thursday, June 30, 2011 - link

    Seconded, a comparison of image quality would be nice. I'd also like to see 1024x768 dropped from testing, who runs that resolution? Looking at a couple of other reviews, the tests were done@ 1680x1050 with good frame rates on Llano. If a game has to be dropped down to 1024 to play then why bother, it's going to look ugly anyway.
  • Musafir_86 - Thursday, June 30, 2011 - link

    -In my place, budget/value systems often bundle with second-hand 15" or 17" CRT (sometimes LCD too) to reduce the sale price. So, I think 1024x768 (and 1280x1024) resolutions are still relevant. :)

    Regards.
  • L. - Thursday, June 30, 2011 - link

    The third world is a dreadful place indeed...
    17 inches *shivers*
  • ppeterka - Thursday, June 30, 2011 - link

    Hey, you dissin' me? My home rig is 17", my work rig is 2x17", and not gonna change soon. I don't want to. I enjoy life even at sub-HD resolutions too...
  • L. - Thursday, June 30, 2011 - link

    Just kiddin', my laptop is 17" too ... 17" of eye-killing 1920*1200 madness.

    No reason to change, except you can get LED pannels for like 130 euros now .. and damn it's good for the movies.

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