Stardock posted the System Requirements for GC3
https://forums.galciv3.com/461330/
but from my experience so far in Insane maps on my system with: i7 2600k, 16GB RAM
game runs.. well much less than ideal, it's slowwww especially when it loads the map or in later stages and I play only with 4-5 other races plus minor ones.
And several times I got a notification for low resources and I had to quit the game so I turned the virtual memory on my SSD.
I never had to do this before GC3 is the only program asked me for more while it doesn't use more than 6GB.
and despite the added virtual memory the game is still slow and sometimes I have to reboot then it works a little better but not fast enough.
so the recommended system requirement perhaps should be higher?
Faster CPU and more RAM?