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Why is +5 volts on pin 9 mandatory for system units and/or graphic cards?

April 26, 2017cards graphic mandatory Pin system units volts

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Why is +5 volts on pin 9 mandatory for system units and/or graphic cards?

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It is becoming common for system management software to interrogate peripheral devices for product type and serial number as a form of asset management. This is usually scheduled for nighttime but if the monitor is powered off then no data can be collected. Providing +5 volts allows the DDC circuit in the monitor to remain active even when the monitor itself is powered off.