Ever since I got my 6900xt (Feb 2021) I am not able to play ACO as there are constant dips in fps and low average fps. This happens weather on LOW or Ultra settings in-game. Since then I have formatted my PC 3 times and always installed the latest drivers. I do not overclock or change the default settings. My windows configuration is as stock standard as it gets. I still get this problem. Other games like AC Vahalla, Call of Duty, Counter Strike, Doom Eternal ect I get high fps as expected. I don't know, am I missing something?
PC Specs:
Asus ROG STRIX Z270F GAMING
Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz
HyperX 32GB 3000mhz
Sabrent 1TB NVMe PCI-E 4.0 (SB-ROCKET-1TB)
XFX Radeon RX 6900 XT Speedster MERC319 RX-69XTACUD9 16GB GDDR6 256-bit PCI-E 4.0
Cooler Master V1000 1000W PSU
Dell S2721DGFA 27" WQHD (2560x1440) 165Hz 1ms IPS AMD FreeSync Premium Pro
Currently also playing Origins. Probably your CPU. I'm playing at 3440x1440 at max settings. Try increasing the resolution scale to put more load on the GPU. See if that helps. I'm also using the 'unofficial' version even though I bought the game. Load times are much better.
AC Origins is badly optimized, period.
Use DXVK (DirectX to Vulkan wrapper) with that game, you will get better frame rate and much better frame pacing.
Your CPU will be holding you back there, and I agree with the posters feedback above also.
DX11: Check
Huge open world with lots of objects to draw: Check
Result: Huge API overhead penalty with radeon GPUs, increasing CPU load, saturating thread and slowing down GPU frame draw time = less fps.