Pyrus said:
Toolafter four albums, Fates Warning switched singers and became a boring prog-metal band. Night On Brocken, The Spectre Within, Awaken the Guardian and No Exit are the only ones worth buying.
As much as I like these albums - especially "The Spectre Within" and "Awaken The Guardian" -, I disagree that they are the only ones worth buying, because I also enjoyed "Perfect Symmetry" very much, but this is - as always - a matter of personal taste. The latter sounds very different from their first releases and it´s definitely not power metal, yet I never considered any of their first four releases power metal either. Well, that´s the trouble with genre labels: 5 people, 10 different opinions. However, the only important question is not how you label a band or an album, but whether you like the music or not.
But back on topic: Jag Panzer´s "Ample Destruction" and Helstar´s "Remnants Of War" have already been mentioned.
Some other albums which - IMO - feature "powerful" metal songs and which you
might regard as power metal are:
Vicious Rumors - "Soldiers Of The Night" (definitely), "Digital Dictator"
Liege Lord - "Master Control"
Chastain - "Mystery Of Illusion", "Ruler Of The Wasteland", "The 7th Of Never" (still my favourite Chastain album), "The Voice Of The Cult", "For Those Who Dare"
Griffin - "Protectors Of The Lair"
Malteze - "Count Your Blessings" (the best song on this album is definitely the title track)
Drifter - "Reality Turns To Dust"