Duel Moniter Setup Questions & Problems?

I am currently just purchased 2, 19 inch acer lcd moniter's and i am looking for options for a duel moniter setup. My system specs are, ASUS k8n motherboard, 1 gb of ram, and radeon x1650 512mb video card. I understand i can take a gender changer and connect it to the back of my video card and plug another moniter into there, but i understand that will slow down my computer greatly. so i was wondering if i could put another video card in my system and install drivers for it and put another moniter on that video card, the other video card i have is, radeon 9600 pro atlantis 256mb. please answer my question, and yes im running xp