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[Raistmer]

HD4870 reports only 256 MB memory for OpenCL

Same host under Vista x86 : GPU reports 512 MB to OpenCL (as should be).
Why 256MB limit still present for x64 SDK version?
How to avoid it for SDK 2.2 ?

Also, profiler reports almost 10 (!) time higher execution times for all kernels under Win7 x64 compared to Vista x86 (same app, same workload).

What is wrong with ATI software under Windows 7 x64 ???

[Raistmer]

When I use good old env variable (that supposed to do absolutely nothing in SDK 2.2, right ?) GPU_MAX_HEAP_SIZE and set it to 512 GPUinfo-like code starts to report 512MB available instead of 256 (Win7x64+Cat 10.10+SDK 2.2).
But app performance still unacceptable. Still ~10 times longer kernel calls.
Should I degrade to prev catalyst ? x64 platforms not supported with HD4xxx GPUs ? Or what? Such poor performance makes GPU completely unusable in this software configuration.

[himanshu_gautam]

Do you face this issue with openCL samples also or with your app only?