Symptom of the Universe Lyrics

by Black Sabbath
I don't understand it, EVERY SINGLE tab i've seen of this is WRONG. I have a Black Sabbath Video and i
SEE him playing it this way. Now, he may have it tuned down or what have you, but the notes are still correct.
Main Riff
G Db G G`Db
Part 2
the break down following part 2
sounds much harder than it really is eh?