ssor> One of Intel' sIntel 486 family of microprocessors (one of the last before the Pentium). The 486DX has a working built-in floating point unit (FPU). The Intel 486sX is effectively a DX with the FPU disabled. The DX has a pin to select the external data bus width (16 or 32). The Intel 487sX is a 486DX with a 486sX pinout. (1995-05-09)