does anyone know where i can get some hd25-1 ii replacement cables? or is it worth it to upgrade to a different cable?

Well basically my old soundcard died and a friend of mine gave me these 1212m's. I'm not that much of an audiophile, so I don't really know all the technical details of how to set it up. Currently my heaphones are HD650s and my speakers are Klipsch promedia 5.1s and I have no idea how to plug my...