Complex sentence: The three major 1xx3 chipset versions (1073,1183, and 1283) all featured the same chip in terms of format support and performance, the only difference being the added ability to record AV sources in the 1283.
Split into simpler sentences: The three major 1xx3 chipset versions were: 1073,1183, and 1283. These were all the same chip in terms of format support and performance, the only difference being the added ability to record AV sources in the 1283.