I would have to put the Radeon 9700 pro up high on the list for perfomance and features.
But really, when you talk all time, we have to at least think back about Hardware T&L with the original Geforce. Shoot or even before that the Rendition cards. (edit, had to look the exact model up for fun - Rendition Verite V2200
). Those were big inovational moments in Graphics chips for sure.
Shoot, many here sure remember times before 3D cards. (pre voodoo) I still have the ATI Mach 64 from back in 1994 when that was ATI's top card.