Using latest 581.80 WHQL driver both rigs. 

Full error:

12:53:49 - SuperFly: Start rendering on device NVIDIA GeForce RTX 5080.
12:54:25 - Warning: Error Rendering in SuperFly.
12:54:25 - SuperFly: Out of memory in CUDA queue enqueue (integrator_shade_surface)
12:54:25 - SuperFly: Rendering time: 35.09 seconds.12:54:25 - SuperFly: Rendering memory: 13555 MB.

Poser RAM usage 22.2GB should be plenty left for windows...

Swap file is 12GB on win11. 2GB was enough when i use win10.