I am starting with OpenCL and want to know which version of ATi Stream SDK I can use . i have ATi Radeon HD 3450 on Dell optiplex desktop
OpenCL will not run on your GPU. It is only beta supported for 4xxx series and full support comes with 5xxx series GPUs.
which card would be best for Dell Optilplex 780.
P.S I working in computer vision/image processing
Your choice would depend on your budget and how much performance is sufficient for you.
This link lists all the 6000 series cards available from AMD. 6990 is the most powerful
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