Hi. I have the same GPU (GTXX275) and also the expresscard version of the EXP GDC (v8.4d).
Seems to work if i put my pci express slot to 1. Generation Mode in the bios (Thinkpad t530 i7)... have you managed to run it in Gen 2/Automatic mode?
Would be cool to compare Benchmarks aswell.
Best,
Anika.