Slow Premiere renders although got better processor.

Hello friends!

I would like to put under your consideration the following issue:

I have a 4 core (8 threads) Intel i7 desktop processor in my one computer. I have a GeForce GTX 1060 6Gb graphics card and I have 56Gb of RAM.

This is my second P.C. since my primary one is a very powerful one.

I changed the processor and put a six core (12 threads) Intel i7 X (extreme edition).

My renders though are exactly the same in terms of speed and maybe a little slower than the 4 core processor.

I checked that Windows 10 can see all 6 cores.

I can see that when I am rendering a short film without the maximum rendering setting enabled, the usable percentage of CPU and GPU is:

CPU: 12%

GPU:23%

I changed the priority settings of Premiere from "Normal" to "High" and now the percentage is:

CPU: Between 18% and 21%

GPU: 26%

But when I was using the four core processor I had a 78% GPU usage (without high priority settings enabled) and a 72% CPU usage. I know that because when I was rendering, I could barely do anything else.

So, how can I optimise CPU and GPU performance so that everything goes to Premiere?

Thank you!

Yiannis.