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[LowProgrammer]

Hi2all

How it is possible to have "80 Stream Processing Units" for ATI Mobility Radeon HD 5400 Series GPUs (e.g. http://www.amd.com/us/products/notebook/graphics/ati-mobility-hd-5400/Pages/hd-5450-specs.aspx) and CLInfo program to give 2 compute inits (Max compute units) ?

Assuming 5 processing elements per 16 stream cores the CLInfo must give only 1 compute unit... Except if there are 8 stream cores per compute unit… What really applies ?

Also what is the wavefront granularity for same series GPUs ? 32 or 64 threads per 4 cycles?

I cannot find any of the above information inside specifications

Thank you!

[MicahVillmow]

A stream processing unit is not a compute unit. There are 40 stream processing units per compute unit and 8 stream cores per compute unit. So that gives you 5 stream processing units per stream core.

[himanshu_gautam]

wavefront size is 32 for 54xx devices.

see sec 4.8.4 of opencl programming guide.