Wow that's a monster rig! As you have an Intel CPU, I am copy-pasting this from another comment:
PLEASE ONLY FOLLOW THIS IF YOU HAVE AN INTEL CPU! If you're not sure, don't risk it. Non-Intel users may see negative performance impacts with no visible gain.
We have debug option to disable a graphical setting we believe may be causing graphical artifact issues on some Intel hardware setups.
It can be force disabled using the console command: rendercapoverride_set 3 1 , then restarting the application. It will persist across reboots.
If issues are experienced after disabling, it can be re-enabled using rendercapoverride_set 3 0, or all graphics settings can be cleared on Windows by deleting the Settings.jcache files in %LOCALAPPDATA%/Jagex/RuneScape
Again, please only attempt to use the above if you have an Intel CPU, but I hope that if you do, it ...
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