The Core 2 brand refers to a range of Intel's consumer 64-bit x86-64 single-, dual-, and quad-core CPUs based on the Intel Core microarchitecture. The single- and dual-core models are single-die, whereas the quad-core models comprise of two dies, each containing two cores, packaged in a multi-chip module. The introduction of Core 2 relegated the Pentium brand to the mid-range market, and reunified laptop and desktop CPU lines, which previously had been divided into the Pentium 4, Pentium D, and Pentium M brands.
The Core microarchitecture returned to lower clock rate and improved processors' usage of both available clock cycles and power compared with preceding NetBurst of the Pentium 4/D-branded CPUs. Core microarchitecture provides more efficient decoding stages, execution units, caches, and buses, reducing the power consumption of Core 2-branded CPUs, while increasing their processing capacity. Intel's CPUs have varied very wildly in power consumption according to clock rate, architecture and semiconductor process, shown in the CPU power dissipation tables.
The Core 2 brand was introduced on July 27, 2006, comprising the Solo (single-core), Duo (dual-core), Quad (quad-core), and in 2007, the Extreme (dual- or quad-core CPUs for enthusiasts) version. Intel Core 2 processors with vPro technology (designed for businesses) include the dual-core and quad-core branches.