Cyrix' 100MHz 486; just like their 66MHz and 80MHz version it's a reversed engineered part and generally didn't perform as well as Intel's DX4/100. Although basic mathematic calculations and Whetstone seem to go very well on the Cyrix 486 processors.

Also note this CPU requires less voltage. This is due a scaled down and improved manufacturing process that generally causes a CPU to scale better with less voltage and thus less heat output. > Read more