Error: No Nvidia graphic adapter found while install Nvidia driver for K20 gpu on machine with 2.6.3

I am trying to install Nvidia GPU driver 319.32 present in the latest 5.5 cuda toolkit on our new machine running linux 2.6.32 kernel with K20 GPU with a PCIe3.0 . But I am getting a error msg NVRM: No Nvidia graphic adapter found. Its not loading even the nvidia.ko module. its says Kernel module load error: insmod: error inserting ./kernel/nvidia.ko

any idea how to fix this issue and install the driver?

Which Linux distro do you install?