Load Resistor; Load Resistor Installation - One Stop Systems PE3R Manual

One Stop Systems
7.9 5v Load Resistor
Here is a summary of why a load resistor is needed on the power supply when using cards that only use 3.3V in the chassis.
In order to create a clean 3.3V and 5V voltage, most ATX power supplies need some current to be used on the 5V line. This means that if a card
only uses 3.3V and no 5V then the current supplied will not be steady and therefore not providing much power.
This small amount of power may only be enough to get the card through configuration cycles, which tricks the OS into thinking that the card is
fully functional. When the applications are started and the main chips on the PCI card start processing data, there is not enough power to
support them and the application or OS crashes or disappears.
Adding a load resistor to the 5V line causes more current to flow in the circuitry which controls the power and therefore enables it to operate
correctly I.e. supplying clean and constant current to the 3.3V and 5V lines. Even though a card might use 3.3V signaling some chips on the
board might be using the 5V for some other function and therefore these 3.3V signaling cards might not need a load resistor.
7.9.1 5v Load Resistor Installation
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