Lag on custom settlements

[Gigan]

How come the custom settlements lag like a , I can handle huge battles on medium graphics but I lag out trying out Minas Tirith

[Scorpius Centaurus]

The only custom settlement I have fought at so far is Isengard and it didn't lag at all. It was awesome! I suggest you upgrade your computer.

[ninja51]

Isengard didnt lag for me, but Whethertop did lag like crazy anytime an arrow was fired. It was beyond strange, I can run the game just fine, I very rarely get lag, and can play certain custom settlements just fine.

I believe it might be specific settlements that have problems

[Liam.]

I lag in Osgiliath really bad. The rest are fine.