[hardware] total newb (me) need help setting up 5.1 surround

[gumbothenerd]

I have a 5.1 channel sound card with the usual 3 audio port mini-jack outputs (front/center/rear) that I'd like to connect to a 5.1 receiver which only allows the usual analog 2 pair red/white (left/right) RCA audio inputs. There are not individual pair inputs for each of center, front, and rear.. just one pair total. There are no digital inputs. How can I do this?

I've been looking for cables/converters/adapters on the internet with little luck. The closest I could find was an adapter that converts the opposite direction by Logitech.