fourcore

Fourcore, often written as four-core or quad-core, is a term used in computing to describe a processor that contains four independent processing cores on a single integrated circuit. Each core can execute its own sequence of instructions, enabling parallel processing of multiple threads and improving multitasking and performance in multithreaded workloads.

The concept gained widespread prominence in the mid-2000s as software began to better exploit parallelism. Intel introduced the Core 2 Quad family in 2007, delivering four physical cores on a single package. AMD followed with quad-core designs in the Phenom II era around 2008. Over time, quad-core architectures became standard in mainstream desktops and laptops and were later adopted in mobile and embedded processors as quad-core systems-on-chip (SoCs) matured.

In terms of architecture, quad-core CPUs may share caches such as L2 or L3 and often use a common memory controller and interconnect to the system memory. Some quad-core designs are true four-core chips, while others may pair two dual-core modules on a single package. Many modern architectures also incorporate simultaneous multithreading (SMT) to present additional logical cores to software, though SMT implementations vary by design.

Quad-core processors offer clear advantages for multithreaded workloads, including video editing, 3D rendering, data compression, virtualization, and heavy multitasking. The actual performance gains depend on software parallelism, memory bandwidth, and power and thermal constraints. In single-threaded tasks, improvements may be modest, as performance is limited by a single core’s speed.

See also: multi-core processor, parallel computing, simultaneous multithreading. The term "fourcore" is often used informally; official product names typically employ "quad-core" in marketing and documentation.