Total noob needs help. Just had these delivered but I've only just realised they're not really intended for PCs but small devices like iPod and PSP. I have an Asus A8N-SLI Premium which has onboard 8 channel sound. All the ouputs are 3.5mm jacks (inc. the 2 channel output which I will be using) so my PC will have to connect to the front of the sub where the only 3.5mm input exists. It appears the sub only has coaxial inputs on the back! D'oh!! Anything else I can do?