alienware M14x 555m 3Gb ?cuda 4 problem installing appropriate driver

Sorry if this has been covered elsewhere (I did try to search but found nothing relevent)

I have just taken delivery of an alienware M14x with the 3Gb 555 card - specifically ordered for CUDA modelling. The installed driver supports only CUDA 3.2 but, not surprisingly, I would like to use CUDA 4. Neither the developer driver nor the standard latest notebook drivers from the NVIDIA site will install (they do not recognise any card but the message appears to suggest that drivers need to be downloaded from the laptop vendor) and Dell have available only the currently installed driver (267.21). Note I did tell setup to use the nvidia card (this is an optimus laptop) but to no avail.

Very frustrating. If anyone knows a workaround I would be very grateful.

Thanks in anticipation of your help.

Just in case anyone else runs into this problem. I found the solution in this thread:

http://forums.nvidia.com/index.php?showtopic=204165

CUDA4 nicely up and running now, although performance on the 555m 3Gb is a little disappointing - but still I can at least develop and compile code now.