Computer doesn't recognize my headset

i just upgraded my cpu, motherboard, and ram. Everything works alright but my headphones aren't being recognized by the system. When i go into the playback device they don't show up. The system is using the AMD HDMI audio drivers and trying to send the audio to the monitor ( my monitor doesn't have speakers ) . iv'e seen other people with this problem on many forums but nobody ever answers back so i haven't been able to figure out whats wrong.