Not too sure what your question is... I assume that you have 4 sticks of 1 gb RAM and that your computer does not recognize that. I also assume that you have a 32bit version of Vista or XP; if that is the case, then that is also the explanation. In order to be able to use more than 3.2gb, you need to be a 64bit o/s, otherwise all you'd see is about 3.2gb.
However, I don't think you should have any problems with 3.2 or even 2gb RAM when playing games even at highest settings.