How did you create the command to start the solver?

If you wrote the command by hand, did you include -np 8 in the command line?

You show Shared Memory Parallel.  ANSYS recommends Distributed Memory as it usually reduces the time to solve.

A good way to create the batch command line is to go to the Start Menu and under the ANSYS folder, use the Mechanical APDL Product Launcher.

When you use the Launcher, there is a tab for High Performance Computing Setup where you can check the Distributed button and type the number of Processors. Then use the Tool menu to see the command line.