Update: Got it running
I downloaded and installed the "Developer Drivers" and "Cuda Toolkit" from this link:
http://developer.nvidia.com/cuda-toolkit-32-downloads#Windows And i'm getting 2.1 Mhash from the cuda cores.
Not sure you need to install the toolkit though.
Running both CPU+GPU in guiminer gets me 2.7 Mhash on avarage.
Will post further updates if i find some tweaked settings or better drivers.
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