Large size allows motherboard manufacturers to pack many features into the board, with a bevy of associated components for us to consider:

Component layout and features vary among motherboard models, depending on the target market, price point and product age. Main power comes to the above example through a 24-pin Extended ATX power connector (12), with the CPU core powered separately via an 8-pin ATX12V connector (13). Another input common on motherboards with dual interfaces for graphics (10) is a standard 4-pin Molex receptacle (14), which offers additional power to the PCI Express x16 slots (10).
There are two common interfaces for graphics cards: Most of today's motherboards have one or even two PCI Express x16 slots (10) to support the latest 3D graphics solutions, while older technology motherboards feature an AGP or AGP Pro slot. Cheap motherboard models have no graphics expansion slots at all, and are designed to work primarily from onboard graphics.
A three-phase voltage regulator (15) is easily identified by three distinct groups of components that work in parallel. Four-phase regulation has become the norm, with each phase adding capacity, so that a five-phase regulator should have up to 25% more load capacity than a four-phase design using equal components. The key to this capacity advantage lies in component equality, as not all components are manufactured with equal specifications. Capacity advantages aside, added components should also reduce ripple current for increased stability under high-stress conditions such as overclocking.
The newest motherboard designs will feature digital voltage regulation, with improved efficiency and reliability that replace the easily identified groups of regulation components above.
We talk more about the individual components below.
what was the different between modern motherboard and traditional motherboard
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