I have been given a Dell A525 Subwoofer and two speakers.  After hooking them up to my Dell Inspirion 531 no sound comes out.  I can't find any drivers for them either.  They only connection appears to be the power (240 volt wall socket) an orange plug (looks similar to the monitor plug) into the back of the subwoofer and a green jack lead from this orange plug, which i connected to the green plug at the back of the PC.  Any ideas?