[Bug Report] GPU/CPU Throttling Mid Gameplay

One thing of note, your CPU is also dropping in usage.  You can easily see the normal period and then a drop when it starts acting up.  This may be related to bios or chipset issues on the CPU instead of the GPU.  CPU for some reason not sending data to the GPU can also cause this kind of issue.  This is an odd issue.  Last time I heard of this was AMD and a Bios update fixed it for a different game.....or it could be a cross program interference, maybe a clean boot of your system and make triple sure only the bare minimum of programs are running.  Also maybe a sfc/scannow of your op system may also be in order.