How do I change my 3 jack Altec lansing PC connection to the new single jack 5.1 jack

[barbsnal]

I have a 10 year old Altec Lansing surround sound system which I want to attach to my new PC. However the new PC only accepts the new 5.1 Jack. Is there a convertor I can buy?

 

[jsmithepa]

Is just matter of finding the correct cable(s) right? If speakers have proprietary connectors, can always cut it and make your own, handy with a soldering iron?