code: func SystemDriverVersion() (string, error) {
  	if C.nvmlHandle == nil {
  		return "", errLibraryNotLoaded
  	}
  	var driver [szDriver]C.char
  	r := C.nvmlSystemGetDriverVersion(&driver[0], szDriver)
  	return C.GoString(&driver[0]), errorString(r)
  }
docs: // SystemDriverVersion returns the the driver version on the system.