How to ID your computer components.
A simple download of a computer profiler will cover all you need to first ID the components and then using that information find out exactly what they are capable of. One such i have always found useful is BERLAC ADVISOR available from http://www.belarc.com/free_download.html
Just follow the lilnk and click on the download box for a free copy.
After it has installed allow it to run and it will present you with a a page of details describing every component both hardware and software that make up your machine.
The problem you are having sounds more like a driver issue which a simple update should cure but before that I suggest setting the graphics to there lowest settings a gradually work them up till you get acceptable levels.