I think it was RedHat.

I had tried Debian first but switched to RedHat pretty quickly afterwards.

(Back then, RedHat had nothing to do with "enterprise", it was just the most polished Linux distro around. Ubuntu didn't exist yet.)

(These days FWIW I use boring old Debian, and I'm not a zealot about it. It works for me. Use what works for you, I don't care. I have a separate machine for gaming and it runs Windows. I know Steam works pretty well on Linux these days but Windows is still less hassle for games.)