Am5x86

The Am5x86 processor is an x86-compatible CPU announced in November 1995 by AMD for use in 486-class computer systems. It began shipping in December 1995, with a base price of $93 per unit in bulk quantities. Before being released, it was in development under the codename "X5". Despite the 5x86 name, it is a 486 CPU, and does not implement 586 or Pentium instructions such as cmpxchg8b. It competed primarily with the Pentium OverDrive, which is a true 586 CPU with all 586 instructions.