xbox 360 on lcd monitor

[nation]

bump. i finally had a need to connect my 360 to my lcd monitor. i got it working fine except i have no audio and i dont know how to connect it in.

i have these cables and i have a 5.1 logitech sound system.



i plan on getting the gateway 30" monitor that had built in speakers so it shouldn't be a problem then but what can i do in the meantime? for the gateway xhd3000 will i need a different cable?