Obviously because you bought the GT220. The 9600GT or GT240 is the lowest card a "gamer" should buy. The 4670 or the 5570 is also good. I'd get a different card or play with the settings until its playable. Don't forget to watch out for your PSU. Don't want to blow it up by asking to much of it.
GT 220 is definitely not a gaming worthy GPU. I think I'm missing some thread posts, as I don't see where the OP identified his monitor (only says 19"). But if it is the 1920x1080 that 4745454b stated, I wouldn't do anything less than an ATI 5770 (which won't be max settings for modern games).
Then again, the older AMD X2 4800+ is going to become a limiting factor as you move forward anyhow.
I have a dell studio, with a 1400x900 res.
It has a 2.1 core 2, 3 gigs of DDR2 ram, and a ati 3650.
I can run empire at lowest settings with only minor hiccups during the campaign mode, and usually without problems on mid to small battles. I figure with what you have you should be able to run it on low, but at this point it is probably dependent on your tolerance to lag. If you are only doing campaign, and you tend to auto resolve battles as you play on, you should be fine. I beat the epic campaign with my computer, but a word to the wise: large battles will really slow you down, and I would probably say that you should never attempt a ship battle with 2 full fleets or more (being the sum of both sides of the battle) with 3rd rate or higher ships of the line, you'll most likely crash to desktop as your fleets become close to each other.
In short, if you want to play the campaign, you can manage, but if you want to play multiplayer, it will probably be rough seas.
The higher the resolution, the much great detail that will be displayed. So if you care about texture settings (and thereby care about image quality) you'd find a higher resolution monitor would make a huge difference in over all image quality (or the appearance to your eyes anyhow).
However, you'd also require a much more powerful GPU.
i didnt know that. mmm yes anyhow i am thinking about getting a geforce gt 240 cause it seems it can run the games i want at good IQ so thats my opinion, so what do you guys reccomend i do for better power and preformance ? for a budget of around 110 USD ?