support@stardock.com I believe this will be the best help.

-Twilight Storm

I can play with a large map, with the distant stars mod. I have a dual-core, and rarely suffer slowdown. I suppose it depends on the type of computer and graphics card though...

I... don't know. Let me check.

Edit: Yup.

ALready tried that. It was the second thing i did.

Get a solid aftermarket cooler OC your cpu to 3.9-4.0 tighten up your ram timings as much as is stable and use core affinity to make sure nothing else is sharing cores with the game. That's about all you can do.

Im running it on a  AMD 7850 (2.8), EVGA 7950 GX2, and 4 gigs...slower system than yours and i havent had any slow downs.....maybe slightly with 6 AI...

Have you optimized your settings?

I have a Core Duo 2.5 Ghz, Nivida 8600 GT, and 4 GB of RAM.

With Distant Stars I get 45-60+ FPS scrolled out.

Depending on the size of the fleets and such. ~15-60+ FPS.

Only I get horrible lag when I have ~ 3 or so end game fleets in the same grav well. And/Or 300+ SC in the grav well. I also play with Large Fleets setting but instead of giving 1.5x, I have it set to 3x.

Usually play 6-10 people also.

Till I optimized my settings, I had bad FPS. Now I can run the game no problem, even increased the Large Fleet setting.

Well...

-VideoAdapterOrdinal 0
-VideoIsWindowed FALSE
-VideoRefreshRate 60
-VideoFullScreenWidth 1440
-VideoFullScreenHeight 900
-VideoWindowedWidth 1024
-VideoWindowedHeight 768
-VideoMultiSampleType 2
-TextureCompressionEnabled TRUE
-TextureQualityForShipColor 2
-TextureQualityForShipData 3
-TextureQualityForShipBump 0
-TextureQualityForModuleColor 2
-TextureQualityForModuleData 2
-TextureQualityForModuleBump 0
-TextureQualityForPlanetColor 2

...

-NVPerfHUDEnabled FALSE
-MeshMock FALSE
-ShowAsteroids TRUE
-ShowElevators FALSE
-ShowDustClouds FALSE
-ShowPlanetRings TRUE
-ShowDebris TRUE
-ExhaustTrailDetail 1.000000
-ShowConnections TRUE
-ShowInfoCards TRUE
-ShowGravWell TRUE
-ShowNames FALSE
-ShowTeamColors FALSE
-ShowMainViewIcons TRUE
-ShowMeshPlayerOwnerIconAlways TRUE
-ShowMeshTeamColor TRUE
-IsEmpireWindowStacked TRUE
-MaxEmpireWindowStackSize 25
-AlwaysShowEmpireWindowFleets FALSE
-ShowEmpireWindowFleets FALSE
-ShowEmpireWindowBackdrop FALSE
-ShowEmpireWindowAllies FALSE
-ShowEmpireWindowEnemies FALSE
-AutoPinPlanets FALSE
-AutoPinCapitalShips FALSE
-AutoPinFrigates FALSE

...

-ShowTacticalGrid FALSE
-ShowCargoShipMainViewIcons FALSE

...

-IsPostProcessSceneEnabled FALSE
-IsShipBrighteningEnabled FALSE

Those are straight from my user.setttings file.

But the main thing you wanna do and what gave me the biggest boost in FPS was turning off Cargo ship Icons, and keeping my Empire Tree Trimed and small. What I mean by that is turning off all the autopin features and manually unpinning Starbases. I also disabled enemy ships from showing in my empire tree since I usually zoom in and mirco my fleet.

Turning off bloom, and ship icons will have you FPS as you zoom in but it does make your ships a bit harder to see. It took me some getting use too.

I also took of elevators, turned off dust clouds and lowerd the quality of planets textures since I dont spend alot of time looking them unless they are buring, which then I cant see half of them anyhow b/c bombing particles.

Its safe to say your performance boost will vary. This is what worked for me. Some others have tried this and gotten no increase. Some have gotten what Ive gotten or better.

Oh another thing you can do gameplay wise is not use alot of SC. Those are by far the biggest source of any kind of lag IMHO. I usually only build by endgame 20-30 carriers at the max. But I tend to go very very heavy on the flak to make up for it.  But if your a huge fan of SC, then maybe docking some when they are not in use will help you.