What case is it? Does it perhaps have a bi-color LED to perform two different functions (like a different color for sleep).

paradigital wrote on 2025-05-14, 21:07:

What case is it? Does it perhaps have a bi-color LED to perform two different functions (like a different color for sleep).

It's a Fujitsu brand-case, a really old one. The front had a Pentium II-sticker on it. Other than that don't really know nor are there any labels etc.

I suppose the led could be a dual-color one.

I would look for the manual of the old board, put cloth tape labels on the appropriate bundles, then get a box of dupont female headers in various sizes, lift the tabs on that monolithic header, then reinsert the boots in the new discrete ones.

1x2 dupont housings
https://www.amazon.com/Raogoodcx-200pcs-2-54m … /dp/B01H0DWTG2/

1x3 dupont housings
https://www.amazon.com/Dupont-Jumper-Housing- … /dp/B0BH4KXXJ7/

1x4 dupont housings
https://www.amazon.com/Gikfun-Dupont-Housing- … /dp/B00R5FOZW2/

As for the "WHAT!? 3 wires for 2 LEDs?!" question, I'd look at "Common ground" as your answer. EG, LED1 and LED2 are driven by discrete positive voltage, with a communal ground wire shared between them.
In VERY old cases, this was done with power and turbo LED, or Power and Keylock LED.

Consult the manual for your old board.

Do you have a multimeter?

Unless theres "smarts" (electronice) in the case front panel, it should be pretty easy to figure out
whats whaat. Jut look for pins connecting when you press the buttons.

Leds can be slightly harder - a 1K resistor in series with either a 5V supply if you have one,
or a 9BV battery will let you try different wires going to the LEDs and figure out their polarity
and if there's any common connections.

That looks like the connector for the FP of a Intel AL440LX board. Sometimes they used a long guy like that. Maybe you can go backwards from there? The Jumper going into itself enables the on-board beeper, so that's the bottom.

Thanks guys!

It looks like the AL440LX-board reference is where things are at. Juxtaposing the labels from the layout for the AL440LX gives me the following to go on:

The one thing I still can't figure out though is why would one of the power led cables connect over to the infrared section? From what I can tell, both of the leds appear - well - like just leds.

Edit:

According to the table for the pins on the AL440LX, pins are labeled thusly (left to right):

Power LED: +5V / Key / GND / Key
HDD LED: +5V / Active / Key / +5V
Infrared: Consumer IR / IrTX / GND / IrRX / Key / +5V

If that is accurate, the Power LED would just be using the Infrared's ground and two pins labeled 'Key' in its own section, and the HDD led would consume one '+5V' and one 'Activity'.

OK, so I decided to follow my intuition and simply inserted the blue cable (originally connecting the power led to the IrDA-GND) into the middle part of the three-pin PWR-LED connector on the motherboard. On the previous case, only two cables connected (the middle section of the connector was empty).

Bingo, power led is working. Out of curiosity I then flipped the connector on the motherboard to see if the LED cares about the position of the red- or yellow cables and I found that the color does indeed change depending on which way around I have it. I suspect this is for some kind of sleep mode thing via the motherboard, but I could just as well just choose the color of the power indicator, since I've never actually managed to make this system sleep / suspend in Windows.

Mystery solved!