Unfortunately the only GPUs that mod works with is those from the 6-series and below, like 6800, 6600 and so on. On all newer series, while you will get that 'quadro' in the GPU name, it wont actually enable any of the quadro features in the driver.

This can be confirmed by opening your driver settings and looking at the 'profiles' list. In real quadros (and successfully soft modded geforce) that list contains entries for 3D apps instead of games, like you will have profiles for 3DS MAX, Maya, XSI and so on. If the list still contains only games, then the mod hasn't worked.