Vast PCB real estate allows motherboard manufacturers to pack many features onto a full-ATX motherboard, resulting in a bevy of associated components to consider:
Retained from our 2006 article, this Socket 775 motherboard still represents the layout of typical high-end products, allowing anyone who’s unfamiliar with onboard components to use it as a guide.
Layout features and details depend on the motherboard’s target market, price point, and a few underlying technologies. Main power comes to the above example through a 24-pin extended ATX (EPS) power connector (12), with the CPU core powered separately via an eight-pin CPU power (EPS12v/ATX12v) connector (13).
Another input common on motherboards with dual interfaces for graphics (10) is a standard four-pin Molex receptacle (14), which offers additional power to the PCI Express (PCIe) x16 slots (10).
Most of today's motherboards have one or more PCIe x16 slots (10) to support the latest 3D graphics solutions, though some use fewer lanes to connect the cards at reduced bandwidth. Entry-level motherboard models have no graphics expansion slots at all and are designed to work primarily from on-board graphics.
A three-phase voltage regulator (15) is easily identified by three distinct groups of components that work in parallel. Modern motherboards typically use a greater number of lower-amperage power phases to provide smoother power under load, a design that also allows unneeded components to be disabled under low-load conditions for enhanced energy savings. Differences in component capacity make it impossible to determine the quality of a motherboard based on its phase count, as even our recent extreme-range motherboard shootout revealed a 12-phase motherboard with a higher rated capacity than its 35-phase competitor.
Motherboards with digital voltage regulators usually lack the distinct groups of components seen above, forcing builders to rely on reviews or manufacturer documentation to determine voltage regulator specifics.