EPOS GSX 300 External Sound Card Review - PC Perspective
Amazon.com: EPOS I Sennheiser GSX 300, Gaming Dac/External Sound Card with 7:1 Surround, High Resolution Audio EQ presets for Gaming, Movies and Music - Audio Gaming Amplifier for PC and MAC Compatible,
EPOS Sennheiser GSP 602 and GSX 300 Gaming Series Review