PC surround sound to ps3?

I have creative a500 5.1 surround sound speakers and want to connect them up to my ps3. The speakers do not have an optical in port so i can't connect that way and i was just wondering if there is any way to connect the black orange and green analogue cables up to the ps3 or if theres some kind of converter to a digital optical cable that i can get that will work with the ps3?

U cant connect it directly to PS3 (unless its 2 channels by using HDMI to composite). U need A/V receiver for that.