Hi guys! First post here! Just discovered this forum! I'm a ig fan of extending the life of old macs and improving newer ones too! I've got a mac pro 1,1 (firmware upgraded to 2,1) running El Capitan. I has the HD 5770 video card from apple but I cannot find where/if I can get hdmi sound out of there. I already know it is possible from mac pro 3,1 and I also know the hardware can do it because it works like a charm in windows 7 and 10. I did some research here but there is just too much information an different methods, I'm just lost right now... Does anyone knows if it has been done before? If yes, is there a guide somewhere? Thanks P.S.: It might be useful to know I bought an HD7970 to put in there but still waiting for it.