Cannot install nvidia graphics driver 440 on Ubuntu 18.04 LTS on thinkpad using Nvidia 1650 Max-Q mobile GPU

[joy.neuro]

I’ve followed the instructions in this link

Both NVIDIA Driver 430.x and 440.x fail to DKMS Install on Kernels 5.4.1 and 5.4.2

You’re running a kernel compiled with gcc 9.2.1 but the system compiler is set to gcc 7.4.0. If you want to keep the current kernel, please switch to the corresponding gcc.

upgraded by gcc and g++ to -9.2.X version and it worked!! hope this helps.