486DX

And Intel Proccessor, cira 1990. A 32-bit MPU with 8-kb on-chip cache and an on-die floating-point unit. A very Good Thing. Usually, when someone just says '486', they're refering to a 486DX as opposed to the other 486 lines like the 486SX, 486SL, 486SLC and 486DLC.

I remember being so happy when my dad ditched the old 386sx 20mhz we had, and bought a brand spanking new 486dx 50mhz. I thought that the FPU was just gonna make DOOM run faster than the speed of light. Then I learned that DOOM was programmed using fixed-point math.