Here's a General Guide to Reduce Lag

[Vampiresoap]

Hi guys, I'm writing this up because I haven't seen anyone else included all of these tricks into one single thread yet. Hope this helps people like me who have struggled for so long with this issue.

1) Go into Task Manager, locate HOI4.exe in the details tab. Set priority to "real time"

2) Press the Windows button + R at the same time. In the opening window type "msconfig". That will put you to system configuration. In there, switch to the "boot" tab. Pick advanced options, and then choose "maximum processors".

3) Go into Documents\Paradox Interactive\Hearts of Iron IV. Here you'll find a text document called setting.ini. Open it, scroll down and you may disable water, sky and bloom by setting them to "no". (for example, draw_water=no) I honestly don't feel the game look too terrible after disabling them, but it's up to you to decide. Do not disable terrain though, as it'll make the whole game go black!

4) Check steam for mods that reduce division numbers in the world. They usually make divisions more expensive to build or something. I'm always a little skeptical about this one because it did not work for me a lot. There's also a mod that combines all south american countries into one big country.

5) Upgrade your CPU! The difference between a 4.0 GHz CPU and a 2.0 GHz one is huge!

 

[ArmChairAttila]

Expert AI mod works well. A configuration menu for the mod pop's up asking for settings. I think the first button is about division composition. Click on it until it says maximum or optimal. What it does is allow the AI to build 40 width + sized divisions. It not only cuts down on division spam but also combat calculations, which in turn does help late game lag.

 

[Vampiresoap]

Expert AI mod works well. A configuration menu for the mod pop's up asking for settings. I think the first button is about division composition. Click on it until it says maximum or optimal. What it does is allow the AI to build 40 width + sized divisions. It not only cuts down on division spam but also combat calculations, which in turn does help late game lag.

That sounds good! Have you tested it yourself? If so, how much did it help you?

 

[ArmChairAttila]

Oh yes, I have with FPS monitors and over 2000 hours of game play with both the mod and vanilla. It does not fix the lag but is noticably better than vanilla.

 

[PrussianPrince]

The first 2 steps shouldn't really help, however the rest is potentially quite helpful.

 

[Vampiresoap]

The first 2 steps shouldn't really help, however the rest is potentially quite helpful.

I don't know if they'd help you, but they helped me tremendously.