I had a 486dx33 and it was unplayable, a few frames per second...

I honestly don’t remember what the frame rate was, but it definitely improved when I upgraded to a Pentium 100. I distinctly remember a buddy giving me some RAM (2x4MB) which allowed me to play on the 486. I was so happy!

The DX2s _were_ a significant improvement over the 486DX, but I’ll admit, I might be remembering the excitement of getting to play Quake at all! The framerate may have been 15-20 fps and I just dealt with it,

The minimum requirements, on the box, were apparently Pentium 75Mhz. 8MB (DOS), or 16 RAM (WIN95).