I just bought Dell U2711, few days back, very nice monitor. This is a display that can be compared with Apple 27" Cinema Display, if not better. 

As I noticed there is 5.1 sound out. —

My question is how can I get my computer audio in to the monitor (except using HDMI in)?

So that I can connect  my 5.1 speaker system with U2771?

I'm using MacPro which has:

• Optical digital audio input and output TOSLINK ports
• Analog stereo line-level input and output minijacks

Thanks