Sauron's power

[Inziladun]

When Sauron wore the Ring, he could not have
had more power than he'd started with. He put a great deal of his own innate power into the Ring, and when he wasn't wearing it, he was diminished. Conversely, when he was wearing it, his power was increased because he had regained his power stored in the Ring.
Even with the Ring though, I don't think he would have been nearly as powerful as Morgoth, who was of a higher order of being.