Yeah, even if the first core gets more load, it isn't maxed, so it's hard to detect a bottleneck here.
He's got a lot of CPU space left too, I don't think he's CPU limited either
Both the GPU and the CPU have headroom, but the FPS is tanked. That's a sign of some bad juju going on in the code...
GPU bottlenecks are really straightforward, but CPU ones are not. If one of your cores is at 90% utilization and probably fluctuates constantly to 95% or so, that means that you are limited by this core in some kind of job in the game system.
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People praising Doom are forgetting how it run before Vulkan patch. You got very CPU limited after 100fps.