Here is some from my list (not power/prog in my opinion):
Aria, Luzbel, Horcas, Baron Rojo, Rigor Mortis, Death, Testament, Overkill, Old Metallica, Megadeth, Flotsam & Jetsam, Dead Kennedies, The Exploited, Black Sabbath, Savatage, Iced Earth, Voivod, Jethro Tull, Rainbow, Uriah Heep, WASP...