Multithreading on CPU

I’ve just installed Mojo and was running the standard Life simulations from the examples, removing the time delay and watching the virtual processor activity level to see how much difference Life3 made compared to Life1. I couldn’t detect any obvous difference in performance and it appeared that Life3 was still only using using one processor at a time instead of all 8. This was when I made the matrix 500 x 900. Am I missing something? It’s an AMD Ryzen 5 3400GE, so with internal GPU, and wasn’t expecting it to use the GPU section.

Thanks.