Microarchitecture
Advances in semiconductor technology reduced transistor size; multicore CPUs have appeared where multiple CPUs are implemented on the same silicon chip. Initially used in-chips targeting embedded markets, where simpler and smaller CPUs would allow multiple instantiations to fit on one piece of silicon. By 2005, semiconductor technology allowed dual high-end desktop CPUs CMP chips to be manufactured in volume. Some designs, such as UltraSPARC T1 used a simpler (scalar, in-order) designs in order to fit more processors on one piece of silicon.