RAM or HDD bottleneck or some other problem

[xarunx]

Hello guys, i just built my new pc with the following specs

I5 8600k
8GB 2800 mhz (its running at 2400 mhz only)
Msi pc pro z370 mobo
cooler master MWE 650W smps
harddisk i didint change (7200 RPM normal HDD connected via SATA)
MSI armour GTX 1080ti
windows 10 pro clean installation

i tried many games, the performance is good but i find these following odd

in pubg 1.0 at ultra i get 90 - 120 FPS @ ultra, 1080p 144hz but i am getting the same at very low settings.

happens same in other games like Hunter call of wild, rainbow 6 siege

In assassins creed origins. it struggles to reach 60fps

is it because of RAM, or Hard disk?
i am not mining or anything.

Any advice is appreciable

Thanks.

 

[haroon453]

have you configured game settings using Nvidia Game Experience? if so then please lower graphics setting from game experience instead of game. Also make sure to update Direct X from "redist" folder within game repository.

 

[xarunx]

Thanks for suggestions I will try them, but steam installs all those by defaults right?

 

[haroon453]

Steam only install games. Nvidia Ge-force experience scan for all installed games and suggest you to "tweak" graphics setting for you based on you hardware.