Is there a definition of "dedicated GPU"?
My memory is a bit fuzzy on this, but from what I remember it was an ATI Mach64 ISA-slot VGA graphics accelerator (2D only, I think). I used it in a 133MHz Pentium MMX (P5) system. This was 1995-ish, I know it was Socket 7, but not much more than that. I also recall having to mail-order and install an additional 1MB EDO memory for a graphics adapter inside a 386 machine prior to that (1991-ish), but I can't tell you exactly what graphics adapter that was.
For 3D, I'm pretty sure it was the Voodoo 1 alongside that Mach64 in a faster Pentium 233MHz in the same socket. I never got around to doing SLI, unfortunately. That held me over until I got an AMD K6-2 with an ATI Fury Maxx. The big game-changer for me was the Tualatin Pentium III which is the first chip I remember actively overclocking alongside a GeForce 64MB DDR2 GPU.
There were several other CPU and GPU combinations in between all of those. I had at least one K6-3 build and T-bird build. Other than playing Unreal Tournament and CS relentlessly, I think the majority of my gaming switched over to Xbox (Halo, Ninja Gaiden, Fable, etc.) around that 2001-2004 era. I still bought some PC stuff, but not as much.