Unfortunately, your post contains little information to answer your question as to whether the OCTO is DOA.
A quicker solution than an angry post would probably be to send an email to support, they can help you quickly and competently.
This is a user forum, so you will not necessarily get an answer from Aquacomputer directly.
Questions that I can answer:

“Are these delicate devices? Do they die if you look at them sideways? Why? How the heck does a brand new solid state device go bad? ”

No, they are not, but any electronic device can have a defect and there are DOAs with every manufacturer, without exception.

“Why do they only include a 5 pin connector even though motherboard USB headers are double row?”

Easy Answer, the 9 pin port on the motherboard is 2 USB 2.0 connectors, so why waste a connector if you only need one.
The right question would be why manufacturers use a 9 pin connector if they only need one USB port.

“The user manual even calls the 4 pin Molex power input a “HDD power plug”, which... it clearly isn't. ”

The 4 pin Molex is very old and was originally just that, the power plug for HDDs.

“This is for a water loop- I can't afford to have janky components controlling it. ”


The Aquacomputer devices are the best you can get on the market for controlling your water cooling, but of course you can buy any other product if you like it better.

I have had 3 water-cooled computers running with Aquacomputer controllers, pumps and flow sensors for years. My Aquaero 6 LT is 8 years old, just like my Aquastream pump. So far I have never had any defects with any of my devices.

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Simple answer, the 9 pin connector exists so that users cannot connect the cables incorrectly.

However, anyone who can read can also plug in a 5-pin connector correctly, so no argument ;-)
The two pins on the right are both ground, and are therefore actually obsolete, as the pin directly next to it is also ground.

The 4 pin Molex connectors are unchanged since their first appearance, so it is quite understandable if they are named after their original use, even if you do not do this, you are still able to understand it.

I've already said something about possible defects and DOA, I won't be able to change your opinion, but I don't have to.

I built my first PC in August 1993 and haven't stopped building computers since then, both privately and professionally, and I can definitely tell you that components or ports on motherboards have always broken ;-)

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Zitat von »SyntacticOperator«

I am aware that the USB headers contain two channels but I have no idea why one row is 5 pins, and the other only 4

The 5th pin on the top usb row is the ground pin for the cable shield wrapping, for which only one pin is required

Zitat von »SyntacticOperator«

Die shrinks have consequences. I/O dies should probably be on something much bigger than 14nm, I'd bet anything under the sun the failure rate of modern chipsets is higher than it's ever been, and it's only getting worse.. When did you ever have a fan header die, and what PC parts were available to build with in 1993?

Do you have any figures on this or is it just a gut feeling?
Just take a look at the figures for DOA or warranty/guarantee, you can find them here and there on the Internet.

The fact is that boards were delivered defective or broke in the past, so I can't see any connection with the transistor size.

As for the components in the 90s, I hate to disappoint you, but they were the same as today.
CPU, GPU, motherboard, RAM, HDD, CD drive, sound card, network cards and a few things that no longer exist today.
Of course, the connections were completely different :-)
My first computer was a 486DX50 with a Matrox graphics card and a 256MB HDD and a Mitsumi CD Rom, the first on the market, the RAM was very small, in the MB range, but I can't remember whether it was 1 MB or 4 MB.

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OP - you are not the first person to complain about the Molex power connector. The OCTO uses a Molex power connector because a SATA power connector cannot deliver the amount of power required. The Octo spec says it can pull 8A at 12VDC and 6A at 5VDC. SATA power connectors are limited to 4.5A at 12VDC and 4.5A at 5VDC. The Farbwerk 360 is another Aquacomputer device that uses Molex power so it can drive 90 LEDs per channel x 4 channels. FWIW, I have several Octo controllers and think they are the best PWM fan controllers out there. While it is possible that you got a dead one, it is VERY unusual. I suggest double checking your Molex power connector with a volt meter.

If you want to talk about janky hardware, the Corsair Commander Pro comes to mind, with its undersized output transistors that get hot and fail, and firmware bugs that were identified years ago and are still not fixed.

Zitat von »SyntacticOperator«

All of the fan headers on my nearly 5 yr old X570 have died, and so I've been using chassis fan hubs and just installed an Aquacomputer OCTO. Unfortunately, it appears to be DOA. It is not detected by the software regardless of being correctly plugged in (with the black wires on the right, on the top side row of the usb port- the 5 pin row), nor do any fans spin. Are these delicate devices? Do they die if you look at them sideways? Why? How the heck does a brand new solid state device go bad? Why do they only include a 5 pin connector even though motherboard USB headers are double row? For a $90 fan hub- so far the experience is incredibly disappointing. The user manual even calls the 4 pin Molex power input a "HDD power plug", which.. it clearly isn't. This is for a water loop- I can't afford to have janky components controlling it.

Can you tell us more about your setup?
If you managed to kill all the headers of your motherboard plus an Octo, there's something extremely off somewhere that needs to be solved before you burn another controller.
As for the single row USB, that's simply to avoid wasting the unused port. you can use it for another device. competitors insist on using two ports for one device for no good reason, or maybe to sell more internal USB hubs i suppose.

Zitat von »Remayz«

competitors insist on using two ports for one device for no good reason, or maybe to sell more internal USB hubs i suppose.

Corsair comes to mind again. I have 2 Lighting Node Cores in my build and they both have 10-pin USB connectors on them for no reason. Because of this, they eat 4 USB ports instead of 2. I have a LOT of USB devices, connected to 3 internal USB2.0 hubs and I greatly appreciate that Aquacomputer uses single-row 5-pin USB connectors on their devices. There is no reason that I am aware of to use a 2-row 10-pin connector on a USB device when it only requires +5VDC, Data (+), Data (-), and Ground.