Try this, it worked for me :
"I'm just posting here because i fixed an issue that a lot of players has :
My game runs at 5/10 fps on very low altought i have a good computer ( RTX 2070super, i7 cpu, 18Gb RAM, thrustmaster t150 wheel etc). You might even have this report when your game crash :
"access violation at address 0x2e1cc875 in module 'dirtrally2.exe' + 0x8dc875. dirtrally2.exe"
I'll make it short for you because i know you are prob tired of trying a lot of solutions :
1) go behind your computer
2) unplug your screen and search for another hdmi port BEHIND YOUR GRAPHIC CARD, it might be hidden behind a plastic cover.
3) Now your motherboard recognise your main graphic device as your GPU and not your CPU, and the game should run smoothly.
i hope this helps, good luck "