'''++f_azazza++''' looks like a A1176 uses the same 18.5V but has a larger amperage at 6.0A. The A1176 power supply is compatible with
Mac mini (Early 2006)Mac mini Intel Core Solo 1.5Ghz, Core Duo 1.6GhzMA205LL/A, MA206LL/A, A1114
Mac mini (Late 2006)Mac mini Intel Core Duo 1.6Ghz, 1.8GhzMA607LL/A, MA608LL/A, A1176
Mac mini (Mid 2007)Mac mini Intel Core 2 Duo 1.8Ghz, 2.0GhzMB138LL/A, MB139LL/A, A1176
Mac mini (Early 2009)Mac mini Intel Core 2 Duo 2.0GhzMB463LL/A, MB464LL/A, A1283
Mac mini (Late 2009)Mac mini Intel Core 2 Duo 2.2Ghz, 2.5Ghz, 2.6Ghz (CTO)MC238LL/A, MC239LL/A, A1283
Mac mini (Mac OS X Server, Late 2009)Mac mini Intel Core 2 Duo 2.5GhzMC408LL/A, A1283
but not the A1176. Most likely not reverse compatible due to a connector etc. issue