Historical clue formulations

• ___-80 (classic computer) — 2015-01-21
• ___-80 (early home computer) — 2012-11-18
• ___-80 (old computer) — 2011-09-02
• ___-80 (classic computer) — 2008-01-04
• ___-80 (old computer) — 2005-01-08
• ___-80 (old computer model) — 2003-11-23