CUDA on Geforce640 works with 304xx drivers, not with default version

[Michael Clerx]

Is this normal? As far as I understand the nvidia naming scheme, the 600 
series comes _after_ the 8 series so I shouldn't be using the legacy 
drivers. However, if I try to run cuda programs with the up-to-data ones 
they all fail to find the device.

Anyone else have any experience with this?
Running Fedora 19, 64 bits

Thanks,
  Michael