Hi Exorcet,
since I upgraded and got a nice clock on the new CPU the 1080 operates at up to 99%. Simplest way to see is using the performance monitor launched from the task manager. It will give you a nice simple overview of whats going on with your system. Using the rift I have it set on the right side of my monitor and take a peek from time to time. If you have a 2nd monitor you can use it. Alternatively Speedfan freeware will record any values you select on a live graph so you can check back after your gaming session.
Any questions please ask, there are never stupid questions :thumbup:
EDIT: I attached a screen showing the MSI afterburner software. See the GPU is almost maxxed out with an O/C on all cores of 4.9 Ghz. The RAM and Pagefile usage is there along with the temps and load of each core