Part of that was the bus and memory speed as well. The 486 bus ran at 33 MHz (the "DX4" is actually only clock-tripled to 100), while the Pentium bus and memory ran at 66.
Yes, I know. Setting the jumpers for the right bus speed for the multiplication was key. This was the time of the fine tuning and over clocking. Asus boards were the best for this job back then.
We kind of marveled back then because MHz meant speed.