I have Dell Optiplex 790 MT with an RX570 8vram, 8gbs ram and a recently installed stock i7-2600k and I'm getting unstable fps in most games especially in Destiny 2 . I've checked CPU temps and done a few stress tests, there isn't any thermal throttling, turbo boost and hyper threading is on. I've also updated the BIOS and checked them. I don't think its a mobo problem. The CPU utility sits very low at 20% to 30% in games even in high priority while the GPU is under very high load. I've checked benchmarks for my specs aswell im underperforming in the expected benchmarks.