97
98
99
From that, to me 99 was the first true 3D engine but I guess 98 was sort of 3D - in any case, 98 and 99 was solid iirc, it didn't affect them much then.
BTW, check this out:
This is 99 apparently....now that's either not really 99, or it's an enhanced screenshot. It's small I know, but the crisp nature makes it look more like 2005 with shoddy player models.