I think the game was meant for i7.
Your ram might be a little low.
I think 10-16GB is recommended.
I think your GPU, however, is probably OK (I think).
I am frankly surprised it runs for you.
I know someone who tries to run the game on i5 with like 16GB and a high end GPU, and he can BARELY get the game to turn on.
For him, it is unplayable, and his box seems a bit more powerful than yours.
If it helps, I did dig out this link...
Might be time for a new box soon!