That's the way I do mine, just make sure it's a thin layer, too much can be as bad as too little, the trick is to get the right amount applied.
You should apply the paste, attach the cooler, then remove i the cooler and check if the paste is squeezed out on the sides this means you have too much.
This is a good review: Best Thermal Paste Application Methods
Sorry, should have post the info in the last post.
Check your BIOS for the (IMC) CPU/NB voltage and post it here.
You can test the CPU core temps with your most demanding game or run a stability test.
If you want to stress the system you can run OCCT.
OCCT stability checking tool
Run the CPU:OCCT test for at least 30 minutes, be sure to monitor your CPU and GPU temps, don't let the CPU go over 66°C.
Set the time before you start.
When its done, pass or fail, it will make some graphs. Post these here as they are useful for analyses.