AMD Radeon HD 7900 Reviews

Discussion in '3D Hardware, Software & Output Devices' started by Arty, Dec 22, 2011.

  1. silent_guy

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    The lower Vt part will usually be faster than the higher Vt. So you can run it at lower voltage for a given performance. Which means that the dynamic power will be quadratically lower.

    Where's the crossover between leakage power increase and dynamic power decrease? I dunno.

    But to say that the low Vt part is worse is too one-dimensional without more information.
     
  2. CarstenS

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    Do you have any idea, what registers GPU-z is referring to? Moreover - what's AMDs official term for those? :)
     
  3. silent_guy

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    It's probably a silicon speed classifier that's burned in the fuses. All chips have test structures to quickly measure a number of key physical parameters during ATE testing. E.g a ring oscillator

    Based on this you can bin a chip into fast/slow bins and within the same bin you can set the desired operating voltage. The former is more common than the latter, but with smaller process variations, the latter is gaining importance.
     
  4. CarstenS

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    Ok, that would qualify for me as some sort of quality measurement for an ASIC. Nothing, at least, I'd as readily dismiss as Dave has done above.
     
  5. silent_guy

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    Calling it 'quality' is really stupid, though. They should have call it 'bogo factor'.
     
  6. Dave Baumann

    Dave Baumann Gamerscore Wh...
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    They are not looking at speed.
     
  7. CarstenS

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    Agreed, for a pop-up box you need something more correct if you don't explain any further.

    They = the registers GPU-z is interpreting?
     
  8. Skinner

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    Tweaking lod bias in dx10+?

    Is it possible? The new Catalyst allow SGSSAA in dx10+ but the automatic lod correction is active.

    Is there a programe to force it for dx10 and -11?
     
  9. fellix

    fellix Hey, You!
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    Only if the application supports multi-sampling under DX10/11.
     
  10. Skinner

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    I know about the SSAA needing ingame MSAA, but I mean the lod bias. There is a slight blurr for now.
     
  11. fellix

    fellix Hey, You!
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    Only on the textured surfaces or the whole screen image? With NV here, I can get blurry image output in almost every game when forcing SGSSAA, until I tweak the game's profile with the proper AA compatibility bits. Manual LOD correction alone is not enough in this case.
     
  12. Skinner

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    Well, mostly on textured surfaces, see;

    http://www.pcgameshardware.de/aid,8...X-10-im-Test-Test-des-Tages/Grafikkarte/Test/ .

    Yes I had nV before and setting different compatibility flags with inspector did the trick.

    Allright, so it's not a matter of lodbias alone, many interference of post processing effects?
     
  13. almighty

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    Even using 4-8xMSAA in DX9 mode with Adaptive anti-aliasing provides amazing anti-aliased foliage in Crysis and Warhead.

    So clean in fact that one has to wonder if SGSSAA is really worth the perf drop..
     
  14. Man from Atlantis

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    I tend to use SGSSAA for shader aliasings, Tssaa and AAA are good enough for transparencies only.. SGSSAA is vital for games like Mass Effect imo..
     
  15. Dave Baumann

    Dave Baumann Gamerscore Wh...
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  16. Grall

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    Why does the demo require a 7900 series card when there's no DX11.1 code in it?
     
  17. fellix

    fellix Hey, You!
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    Virtual texturing via PRT?
     
  18. Jawed

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    The link for the video doesn't work.

    Will the source code be posted?
     
  19. Rodéric

    Rodéric a.k.a. Ingenu
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    Damn it!
    I planned on making a realtime version of ptex myself...

    Are you going to make it open-source ?
    That could be a massive help for game developers !
     
  20. trinibwoy

    trinibwoy Meh
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