Radeon HD 6850 with 960 and 1120 Shaders: TessMark and ShaderToyMark Comparisons



Radeon HD 6850 + ShaderToyMark
ShaderToyMark + HD 6850 (960 and 1120 shaders processors), source



As you may know, some Radeon HD 6850 have been sent to the press with 1120 scalar processors instead of 960. KitGuru has published a comparative article between HD 6850 with 960 shaders processors and HD 6850 with 1120 shaders processors.

Radeon HD 6850 with 1120 cores
A radeon HD 6850 with 1120 shader processors

1120 shader processors means 160 scalar processors in more or an increase of shader computing power of 16%.

ShaderToyMark is a pure and really intensive pixel shader test. Most of shaders used in ShaderToyMark are math shaders (few or not texture fecthes at all). ShaderToyMark is nearly a GPU computing application!

And guess what? There is exactly an increase of 16% between both versions of the HD 6850 (see the chart above).

Radeon HD 6850 + ShaderToyMark
ShaderToyMark: HD 6850 with 960 shaders score

Radeon HD 6850 + ShaderToyMark
ShaderToyMark: HD 6850 with 1120 shaders score



In TessMark 0.2.2 (OpenGL 4 tessellation benchmark), it’s another story. In normal tessellation mode (which correspond to a tessellation amplifation factor of X16) the difference is around 14% which sounds normal. But in moderate tessellation (factor X8), the difference jumps to 36%. Don’t ask me why, I currently have no HD 6800 series in hands so I can’t test TessMark to see how it behaves with HD 6850 / HD 6870.

Radeon HD 6850 + TessMark
TessMark + HD 6850, source


From TessMark comp. table, here are the score of some Radeon HD 5000 series in moderate tessellation:
- Radeon HD 5770 (MSI R5770 Hawk, 800 shaders, gpu core:875MHz): 20366 points
- Radeon HD 5870 (1600 shaders): 27000 points

I just received from Zardon, the guy behind KitGuru, the TessMark scores for a Radeon HD 6870 (1120 shaders, gpu core: 900MHz):
- Moderate tessellation: 23199 points
- Normal tessellation: 8342 points

The HD 6850 has a GPU core clock of 775MHz. Let do some linear math for the moderate tess level:

  • a Radeon HD 6850 1120 shaders with a core clock of 875MHz would have a score of around 21100 points: the score is a bit above the MSI R5770
  • a Radeon HD 6850 1120 shaders with a core clock of 900MHz would have a score of around 21700 points: the score is not too far from the HD 6870



In normal tess level, MSI R5770 Hawk gets a score of 7515 points, whereas the HD 6870 scores 8342 points.

  • a Radeon HD 6850 1120 shaders with a core clock of 875MHz would have a score of around 7990 points: the score is a bit above the MSI R5770
  • a Radeon HD 6850 1120 shaders with a core clock of 900MHz would have a score of around 8220 points: the score is not too far from the HD 6870



At first sight, the scores of the Radeon HD 6850 with 1120 shaders look normal. Actually, seems there’s a problem in the TessMark score of the 6850 HD with 960 shaders. This score should be higher like around 16000 points in moderate tessellation. But I stop here because I don’t have a HD 6850 nor HD 6870. Maybe there’s a bug in TessMark, or in the OpenGL driver of Catalyst 10.10 or in the measure… If someone has a clue, the comment section is there for you!





[ Subscribe to Geeks3D latest news by email ]

Geeks3D.com

↑ Grab this Headline Animator