But always refer to manufacturer's instruction. The main companies are Intel, Advanced Micro Devices, Cyrix, and Motorola. 80286 for 286 motherboards for IBM PC ATs and clones. 80386, 80386SX and DX for 386 motherboards. 80486DX, DX2, and DX4 all have a math coprocessor inside the chip.
All subsequent chips made afterwards feature a math coprocessor.
80586 or Pentium. A 32-bit microprocessor introduced in 1993, and contains 3.1 million transistors, nearly three times the number in a 80486 chip. 80686 or Pentium Pro, is the sixth generation microprocessor. It is very different in structure from the Pentium. With superpipelining, dynamic execution, and on-chip L2 cache, it can perform at nearly twice the speed of the 80586 microprocessors.