I don't know a lot about Mac hardware, but I would assume that this is because the GPU in that unit is slower than the CPU? In my experience, the GPU is usually better, though, so someone else may know more.
Can you post an MD5 benchmark (-d -m 0) for both CPU and GPU?
EDIT: My apologies - I meant (-b -m 0)!
Can you post an MD5 benchmark (-d -m 0) for both CPU and GPU?
EDIT: My apologies - I meant (-b -m 0)!
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