Modchip

A modchip (short for modification chip) is a small electronic device used to alter or disable artificial restrictions of computers or entertainment devices. Modchips are mainly used in videogame consoles, but also in some DVD or Blu-ray players. They introduce various modifications to its host system's function, including the circumvention of region coding, digital rights management, and copy protection checks for the purpose of using media intended for other markets, copied media, or unlicensed third-party (homebrew) software.

Modchips operate by replacing or overriding a system's protection hardware or software. They achieve this by either exploiting existing interfaces in an unintended or undocumented manner, or by actively manipulating the system's internal communication, sometimes to the point of re-routing it to substitute parts provided by the modchip.

Most modchips consist of one or more integrated circuits (microcontrollers, FPGAs, or CPLDs), often complemented with discrete parts, usually packaged on a small PCB to fit within the console system it is designed for. Although there are modchips that can be reprogrammed for different purposes, most modchips are designed to work within only one console system or even only one specific hardware version.

Modchips typically require some degree of technical acumen to install since they must be connected to a console's circuitry, most commonly by soldering wires to select traces or chip legs on a system's circuit board. Some modchips allow for installation by directly soldering the modchip's contacts to the console's circuit ("quicksolder"), by the precise positioning of electrical contacts ("solderless"), or, in rare cases, by plugging them into a system's internal or external connector.

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