Hey there @totaleclipse , thanks for getting in touch about this, and welcome to the forums! I understand you're getting a crash to desktop when trying to enable both FSR and HDR at the same time. That's most unusual! I don't see this reported internally yet, so I'd really like to investigate this.
So we can start from the same baseline, can you start with the steps in the troubleshooting guide for me? In particular from the guide, please make sure you are running the game with administrator rights, you've verified the game files, you've got your graphics drivers and Windows install fully updated, and you don't have any background programs which could interfere with the game (such as mods, or system/graphics optimisers).
Once that's done, if the crash still happens, can you also see our system files support article? Let me know once you've got the two files it describes prepared, and I'll open a support ticket you can use to send them across to me. That'll help me to diagnose the crash, and report it internally.
Let me know if I can clarify any of these steps, and thanks once again for reaching out 
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