Update CUDA toolkit from 5.5 to 6.0

Accelerated Computing CUDA CUDA Setup and Installation
1

I work on Ubuntu 12.10 64bit. CUDA devices are GeForce GTX 480 and Tesla C2070.
I installed latest drivers for the GPUs and updated cuda toolkit from cuda5.5 to cuda6.0.

Previously, my program can compile and run correctly. But now I have error:
no CUDA-capable device is detected src/devicemain.cu 40
line 40:

gpuErrchk(cudaEventCreate(&start));

and

cudaGetDeviceCount(&count);

returns count=0.

I did something for the update.
I edited .bashrc
export PATH=/usr/local/cuda-6.0/bin/:$PATH
export LD_LIBRARY_PATH=/usr/local/cuda-6.0/lib64:$LD_LIBRARY_PATH

and the makefile:
-L/usr/local/cuda-6.0/lib64

What else need I do?

Thanks!

2

What happens if you run:

nvidia-smi -a

?