He started work at Commodore in 1983 as an engineer under Bil Herd. His first project was to help complete the TED systems comprising Plus/4, C16 and more. After completing the Commodore 128 Bil Herd left the company and Dave Haynie was promoted to chief engineer in the low-end group. After Commodore acquired Amiga, Dave Haynie ended up primary engineer on the expandable A2000 computer. Later, he joined Bob Welland on the A2620 CPU module, and launched the follow-up A2630 the year thereafter. These were delivered in the A2500/20 (1989) and A2500/30 (1989).