I'm playing an extra long game(whatever the option is that's the next one up from "Normal" on time length), and now that I'm into the 1900's its just lagging like crazy. Its to the point that I keep having to reset my comp every few turns because it just freezes permanently. Is there just too much memory coming from this one extra-long game that's causing it, and is this a regular prob when you play long ones? Or does my comp just suck?
The late game tends to slow any computer down as there are simply more cities, units, borders, etc to deal with. I don't know if game speed has any effect on it.
I don't know what version of the game you're playing, but if it's unpatched vanilla Civ, I
highly recommend you get the 1.74 patch. My computer is very weak for games, and Civ doesn't exactly run smoothly; but the memory usage adjustments they made in the patch made a massive difference for me.
In my current game, I evolved on a large continent with two other civs. There is another large continent in the game with three civs on it. I am just about to complete a big ground war, rubbing out the two civs on my continent, but I'm not in a position to begin an overseas war yet. My ultimate goal is to invade the other continent and win with domination, but my short term plan for the next few hundred years is to almost totally demilitarize and focus on building my economy, science and culture, so that when I'm ready to invade the other continent I'll have a decent tech advantage. My current tech level is such that my strongest unit is grenadiers, and I just discovered steam power.
My question is: what combination of civics will best enable me to achieve this goal?
This question is highly situational. Furthermore, it seems like your plans are too varied and lengthy to choose just one set of civics to carry them out with (especially if you are playing a Spiritual leader, or own the Cristo Redentor wonder). I suggest you take it to the
Strategy & Tips subforum. If you create a thread there with screenshots and/or a copy of the savegame, the lovely folks at this here website will help you out sharpish.
(But a quick answer would be thus. If you are looking to build up your economy, it depends on whether you are using specialists or Cottages more. If specialists: Representation, Bureaucracy, Caste System, Mercantilism, Pacifism/Organized Religion. If Cottages: Universal Suffrage, Free Speech, Emancipation, Free Market, Organized Religion/Free Religion. If you are looking to build weapons: Police State, Vassalage/Nationhood, Slavery, State Property, Theocracy.

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