OpenCL on ATI HD 4870X2

[chestertech]

OpenCL doesn't work on ATI's two head cards. Test says "device error".

[Springdream]

better you try a CUDA compatible card.
I got a GTX460 especially for that purpose...

[Admin]

What version of Similarity do you use ?
We testes latest version (1.6.0 build 1134) on AMD/ATI 6950@6970 it works fine and have very effective perfomance.



3 times faster when single core of Intel I7-2600

Send us logs from "%appdata%\Similarity" (enter in Explorer), we think they contain some error details.

[chestertech]

Sim 1.6.0.1134 on Win7 x64 Catalyst 11.4
Log:
Amd APP - ATI RV770

Ati RV770 version CAL 1.4.1353 (Opencl 1.0 Amd-APP-SDK-v2.4 (595.10))
Process:418 failed [-2147467259]

[chestertech]

And any news on this?

[Admin]

Please try 1140 build it has some exta logs about supporting images, problem in sending data as textures to videocard.
We tried test on 4550 but it doesn't have image support and use other path to receive data. And it works ok.

[chestertech]

Same log as above.
I forgot to say that programm sees two videcards on board

[hsei]

Build 1141 no longer shows "calculation error" in benchmark. But calculation time and CPU load is roughly the same with and without OpenCL enabled.

[chestertech]

Where did u get 1141? Is there closed beta testing?

[hsei]

Just follow the download link in "news - beta version 1.6.0". It has the latest build sometimes mentioned with an addendum in that thread, but often not.

[chestertech]

1141, same as above, but with string - "no images support"

[Admin]

1141, same as above, but with string - "no images support"

Thanks, it's all we need.

Build 1141 no longer shows "calculation error" in benchmark. But calculation time and CPU load is roughly the same with and without OpenCL enabled.

Speedup seen only on big amount of files (>1000) and only on "precise" algorithm. It uses one of the working threads (Options -> Misc. -> Performance: "auto" = processor cores * 2) to work with OpenCL device and don't use CPU, all other threads do work as usually on CPU. In this method we have all power of CPU + OpenCL device.