I have been having issues with my system recently. For a while, the GPU would not down clock when not in use and stuttering was occurring occasionally. However, in my attempts to remedy the issues, I have come across something far worse. My GPU usage will go down to 60% in game and my frame rates will tank. Going from the high 80s to 30. It may jump back up to 60 momentarily, but then lurches right back down. My cpu isn't issue, as I've run 24hr prime tests to check its status (i7 8700k at stock). I have 16gb of 3000 mhz ram. The mother board is an Gigabyte gaming 5 Z370. The PSU is an 850W EVGA G2. Plenty of air flow, as the temps never exceed 70, usually peaking in the mid 60's on the GPU. The CPU is cooled by a Corsair H100i V2 in push exhausting from the top of the case. Games tested, Just Cause 3, Crysis 3, and Battlefield 1. None run properly, even at low settings 1080p. The GPU isn't overclocked.