I was thinking you had a 64, and a 754 board. Nevermind that, sorry i been on stuff all day, not paying as much attention as i should. Well, im sure you done your OC on that XP. Since thats all their good for. If its just not working with your needs, you can go with a howl new mobo, and a moderate processor. Since your working on your master rig also.
I think doing that would be a good idea. Having somthing pretty fast to go along with your master computer.