Most ATX motherboards have those same pins for 'interfacing' with the computer case... depending on the manufacturer they vary on position (hence loose wires at the case end) but never function. So i guess there is a standard somewhere.

they usually looks like this: enter image description here

and you connect wires like these: enter image description here

I looked on the ATX standard but there only seems to be board sizing and the power connector.

I'd love to have the specs for everything on that bundle... but if not, to unblock my work i'd just need to know now the LED (power_led, or p_led) specs. Do I need a resistor? or just a led? which leds are compatible? 5V? 3V?


Out of all the manufacturers I have seen Intel to follow a standard. Few manufactures like Asus, Gigabyte and others follow them also in their motherboard designs.

While Asus follows the Intel standard on their micro-atx cheap boards, I have seen them use an intermediate connector to make front panel connections easy. It was called Q-connector. I believe that the first picture in your post if of Asus motherboard with Q-connectors.

enter image description here

I believe that the LEDs used in such cases are 5v LEDs with built in resistor.

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    \$\begingroup\$ The resistor is in the motherboard. I have wired plain-old T 1 3/4 LEDs to a motherboard header in the past, and they work fine, so the current limiting cannot have been in the resistor. \$\endgroup\$ – Connor Wolf Jan 21 '13 at 4:34
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    \$\begingroup\$ @FakeName I have commercially built and sold workstations, servers, storage and haven't seen such an issue. Motherboard manufacturers may include a drop resistor on their motherboard but they do not completely rely on it when various color LEDs came to case fashion including blue LED. Do you know what value resistor is on your motherboard? \$\endgroup\$ – Chetan Bhargava Jan 21 '13 at 4:47
  • \$\begingroup\$ I don't know what the motherboard resistor value was, but when I was younger (and into case modding), I swapped out most of the case indicator lights in most of the computers I had for off-the-shelf blue LEDs, and everything worked fine for years. \$\endgroup\$ – Connor Wolf Jan 21 '13 at 11:50
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    \$\begingroup\$ Realistically, most LEDs are plenty bright with anywhere between 2-20 mA of current, so the different \$V_{f}\$ doesn't really matter, as long as the LED is high-brightness. \$\endgroup\$ – Connor Wolf Jan 21 '13 at 11:52

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