Hey im very new to community and have to say multi boxing is the most fun ive had in WoW in a long time. Anyway im trying to 3 box shamans my system specs are as follows

Intel celeron 3.33GHz

2 gig of memory

GeForce 8600 GT 512 MB

Now i know this isnt the best pc in the world hey it may be even close to the bottom but its what i got. Right now i run 3 shamans but my fps on each is anywhere from 7-15 tops. I was wondering if their was anything at all i could do with this system that would make it better without having to buy a whole new PC. Looking for cheapest way out basicaly. ANy help would be appreciated. thanks in advance