Runs pretty good for me on laptop win7 sp1, i7m-3520m proc, 8Gram, nvidia quadro k1000m, ssd. Crash every once in a blue moon if I play for days without restarting but not much lag if any with huge fleets. Used to lag/crash on my older machines with less ram/cpu. I even leave norton running.

I do not get very much lag, no matter how many units are on the map...

Not until I research either one of the orbital refinement techs, or a trader tech; resulting in those little ships flying around...

Once the trader/merchant/refinery ships start appearing on the map, then it starts getting all bogged down, and ONLY after those ships start appearing.

Its annoying as heck, so I don't research any of those unless I am close to winning cause I don't want them slowing things down for me.

I'm playing an the following...

Intel Core i5-2500K at 4.6ghz

8GB DDR3-1600

eVGA GTX 770 FTW 4GB

Plextor SSD

Win 7 Ultimate