SOLVED. Adult SciFi/ Space opera, read in late 90s. Massive computer owns universe, vaguely remember ending. Spoilers ahead. [s]

[Brian]

I read a space opera (possible trilogy) in late 90s/early 00s on paperback.

I think there was a massive AI/computer spanning across space and it controlled things in a bad way. A unique group of 3-5 beings/people assemble together to try and fight it. They travel somehow to the home base of the computer which I seem to think is in a long tunnel -- as if they were walking through a massive (dark) data center. (view spoiler)[They solve some very difficult challenges that they are uniquely able to solve. They are successful and save the galaxy (hide spoiler)].

I wish I knew more details -- that's why I'm checking with you all. Thank you!

[Sue]

The "Rings Of The Master" series by Jack L. Chalker? The first book is Lords Of The Middle Dark.https://www.goodreads.com/book/show/5...

[Brian]

Sue - you are right! How amazing that you figured that out! I remember the cover on the final book for sure - that must have been what I was trying to describe in my hint. And, wow, this is a fairly obscure book series, since I can't find a detailed plot summary at wikipedia or wikia or anything. Maybe I need to re-read and contribute something there. Thank you so much!