CUDA HELP

Hi guys,

I am trying to run a CUDA piece of code which is a simple Hello World program on the NVIDIA Tesla. I know for certain that the NVIDIA Tesla device is connected as when I try /bin/lspci it shows a long list of connected devices ending with the Tesla units which ends with the code seen below.
30:00.0 3D controller: nVidia Corporation G80 [Tesla C870] (rev a2)

However when I try running the basic Hello world program that is supposed to mangle the hello world in the device(GPU) and then print the mangled gpu code on the host, it never gets mangled. The hello world that I am trying to get working is the first example found on: http://forums.nvidia.com/index.php?showtopic=90044
I know that the code for the Hello World is correct.

So in short, even though when I do nvcc blah.cu there is no error; when I try and execute ./a.out the output is never mangled, implying that the gpu code is never executed Only the CPU code is functional

Am I supposed to be specifying the port number to which the Tesla is connected or does the computer automatically know it? if so how could ispecify the port number? All the examples that I see online seem to assume that the system knows which port the GPU is connected to.

Also wrapper functions such as CUDA_SAFE_CALL do not seem to work. Is the because wrapper functions need a special header file to be included in the code?

Thanks in advance for any help!