I used to play with 256mb ram and had to use half the screen resolution, otherwise I would lag like utter *** when a member of the opposite faction was anywhere near ( still lagged with that though ). Get more ram, if it still lags, turn down the settings and save up for a GPU. ( £60-80 will let you play it fine, 100+ if you want extra fps which you can't differentiate. )
Thats pretty good advice but what was the question weeman?
I think you might have gone to reply to another post and posted a new thread by mistake?