What case do you have?

Normally cases only have a single HDD LED and consequently motherboards only support a single LED connection as well.

How many HDDs you have?

With some HDDs, you can connect a LED to the drive itself, see eg. Seagate ST1156/1133/1111-A :

1 Remote LED
2 ----------
3      A   B
4    +---+---+    Default jumper at C-D for LED mounted on drive PWA
5    | * | * |    To use remote LED, remove jumper and extend B (Anode)
6    +---+---+    and D (Cathode).
7    | * | * |
8    +---+---+
9      C   D

Shponglefan wrote on 2025-09-03, 12:00:

What case do you have?

Normally cases only have a single HDD LED and consequently motherboards only support a single LED connection as well.

That's the problem - I don't know. ^^; It's some unknown brand. There's no emblem or logo or anything. It was listed as such on eBay.

But yeah, I always figured there was one only. So was surprised to find three.

Grzyb wrote on 2025-09-03, 12:04:

How many HDDs you have? […]
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How many HDDs you have?

With some HDDs, you can connect a LED to the drive itself, see eg. Seagate ST1156/1133/1111-A :

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1 Remote LED
2 ----------
3      A   B
4    +---+---+    Default jumper at C-D for LED mounted on drive PWA
5    | * | * |    To use remote LED, remove jumper and extend B (Anode)
6    +---+---+    and D (Cathode).
7    | * | * |
8    +---+---+
9      C   D

Three. And interesting. Had no idea you could do that. Mine only list Cable Mode or Limit alongside Master and Slave. And one is a Samsung.

Led is / was sometimes found on ide controllers as well.

See for instance, this one, has J1 connector for this.
https://stason.org/TULARC/pc/hard-disk-floppy … IDE-MASTER.html

wierd_w wrote on 2025-09-03, 13:09:

Led is / was sometimes found on ide controllers as well.

See for instance, this one, has J1 connector for this.
https://stason.org/TULARC/pc/hard-disk-floppy … IDE-MASTER.html

Now that you mention it, I do recall seeing J1 and J2 in the manual. I'll take a closer look. Thanks. 😀

wierd_w wrote on 2025-09-03, 13:09:

Led is / was sometimes found on ide controllers as well.

See for instance, this one, has J1 connector for this.
https://stason.org/TULARC/pc/hard-disk-floppy … IDE-MASTER.html

Ahh. Unfortunately the cables aren't long enough to reach them. 🙁

DustyShinigami wrote on 2025-09-03, 12:15:

That's the problem - I don't know. ^^; It's some unknown brand. There's no emblem or logo or anything. It was listed as such on eBay.

But yeah, I always figured there was one only. So was surprised to find three.

Do you have a picture of the case? I'm curious to see what it looks like.

Shponglefan wrote on 2025-09-03, 14:49:

DustyShinigami wrote on 2025-09-03, 12:15:

That's the problem - I don't know. ^^; It's some unknown brand. There's no emblem or logo or anything. It was listed as such on eBay.

But yeah, I always figured there was one only. So was surprised to find three.

Do you have a picture of the case? I'm curious to see what it looks like.

Sure.

I would just connect one LED. It May Look weird if three of them Flashing synchroniously. However you can try to connect them in parallel to one Connector, with a little Risk of overcurrent on this circuit. (60mA vs. 20mA, depending on the LEDs)

AncapDude wrote on 2025-09-03, 15:23:

I would just connect one LED. It May Look weird if three of them Flashing synchroniously. However you can try to connect them in parallel to one Connector, with a little Risk of overcurrent on this circuit. (60mA vs. 20mA, depending on the LEDs)

I mean, I'm sure it would give me a sign if it's overcurrent, right...? But how would one go about connecting them in parallel to one connector? I don't think it would look that weird though. I mean, the LEDs are there on the front, from top to bottom, so it would be great if I could get them working. 😀

Or, just make a small driver circuit board.

A 'reapplication' of a level shifter logic circuit would suffice.

Input signal is the motherboard HDD LED pulse.
'level shifted' output is the higher max current supplied with a voltage regulator and the 5v molex connector. (Say, diskette power rail.)

You can drive a shitload of LEDs that way.

wierd_w wrote on 2025-09-03, 22:27:

Or, just make a small driver circuit board. […]
Show full quote

Or, just make a small driver circuit board.

A 'reapplication' of a level shifter logic circuit would suffice.

Input signal is the motherboard HDD LED pulse.
'level shifted' output is the higher max current supplied with a voltage regulator and the 5v molex connector. (Say, diskette power rail.)

You can drive a shitload of LEDs that way.

I have absolutely no idea how to go about doing that or where to even start. ^^;

It would be fun to use a VU meter type circuit and use the HDD signal as an input. I wonder if that would work properly? It'd look cool if it does.

I have a case that has 10 HDD LEDs and I was wanting to try populating them all, but populating them is hard. Specific cards and drives; ugly, useless combos and such. Really hard to make them all active at once, too. Some circuitry sounds like a good alternative, hadn't considered this before.

The easy solution is to wrap up the unused ones and tuck them away. No monkey-business required*, since they don't have a function. I have 2 Antec Super Lanboys next to me, and they have 3 LEDs (G,R,Y) and only 2 are used, because the computer(s) inside don't offer more than the standard PWR, HDD lights.

DustyShinigami wrote on 2025-09-03, 22:43:

wierd_w wrote on 2025-09-03, 22:27:

Or, just make a small driver circuit board. […]
Show full quote

Or, just make a small driver circuit board.

A 'reapplication' of a level shifter logic circuit would suffice.

Input signal is the motherboard HDD LED pulse.
'level shifted' output is the higher max current supplied with a voltage regulator and the 5v molex connector. (Say, diskette power rail.)

You can drive a shitload of LEDs that way.

I have absolutely no idea how to go about doing that or where to even start. ^^;

A level shifter of this kind needs only be one direction, making it very simple.

You put the HDD LED's input signal on the collector of a transistor, which makes the transistor activate when the HDD LED is energized, and deactivate when it is not. You use a transistor that can handle a larger current flow then the HDD LED header can provide, so that you can drive the parallel HDD LEDs from the signal emitted from that transistor.

See also, here.

https://www.digikey.com/en/blog/logic-level-shifting-basics

Instead of a higher voltage source, you offer a higher current source. (Or, use higher voltage and run the LEDs in series, but meh.)

It's functionally the same kind of thing as a bus transceiver chip, and such a chip could probably be abused here, since we dont really care about isolating voltages, just the amount of charge, and in isolating the LED header from having to deal with so much drain. You can instead use the ground line from the floppy power connector.

Say, one of these 1 bit buffers. You can get 10 of them on a reel of tape for cheap.
https://www.digikey.com/en/products/detail/te … 1G07DCKR/432005

wierd_w wrote on 2025-09-04, 02:56:

A level shifter of this kind needs only be one direction, making it very simple. […]
Show full quote

DustyShinigami wrote on 2025-09-03, 22:43:

wierd_w wrote on 2025-09-03, 22:27:

Or, just make a small driver circuit board. […]
Show full quote

Or, just make a small driver circuit board.

A 'reapplication' of a level shifter logic circuit would suffice.

Input signal is the motherboard HDD LED pulse.
'level shifted' output is the higher max current supplied with a voltage regulator and the 5v molex connector. (Say, diskette power rail.)

You can drive a shitload of LEDs that way.

I have absolutely no idea how to go about doing that or where to even start. ^^;

A level shifter of this kind needs only be one direction, making it very simple.

You put the HDD LED's input signal on the collector of a transistor, which makes the transistor activate when the HDD LED is energized, and deactivate when it is not. You use a transistor that can handle a larger current flow then the HDD LED header can provide, so that you can drive the parallel HDD LEDs from the signal emitted from that transistor.

See also, here.

https://www.digikey.com/en/blog/logic-level-shifting-basics

Instead of a higher voltage source, you offer a higher current source. (Or, use higher voltage and run the LEDs in series, but meh.)

It's functionally the same kind of thing as a bus transceiver chip, and such a chip could probably be abused here, since we dont really care about isolating voltages, just the amount of charge, and in isolating the LED header from having to deal with so much drain. You can instead use the ground line from the floppy power connector.

Say, one of these 1 bit buffers. You can get 10 of them on a reel of tape for cheap.
https://www.digikey.com/en/products/detail/te … 1G07DCKR/432005

Hmm. Would something like that require soldering on though? That's a bit out of my expertise and comfort zone.

If you're going to start coming up with circuit ideas or whatever, it might be pertinent to point out IDE activity signals are active low (meaning the LED anode is usually connected to positive voltage and the cathode gets toggled between high/low).

getting signals from the IDE ribbon would let you know which specific devices are getting activity... but would require significantly more logic.

You would need to grab when the bus was busy, then also query the value of the cable select line to determine which of the devices was talking, and use an OR gate to get two discrete signals, then drive those with buffers.

You'd need a circuit board for each IDE cable.

The project I suggested would just drive multiple LEDs from a single logical signal, by providing them with the extra current they need.

A simple driver attached to the motherboard HDD activity LED header is all that would be needed, plus a molex power terminal, and a voltage controller IC. All that could easily fit on a 1" protoboard.

30 Years ago I connected the HDD LED to the IDE onboard controller and the turbo LED to my SCSI controller.