It's an aux power connector for some ATX motherboards. It is NOT an AT connector.

Ahh that explains it. Obviously I have no idea what I'm talking about yet! Thanks for clarifying.

Also worth mentioning some ATish (late LPX) motherboards have 3 Px connectors.

Just before the ATX standard appeared Intel provided a new standard for its Pentium Pro LPX platform, it didn't take off but it provides soft On (no external power switch), idle power and a 3rd Px connector for a 3.3v rail.

Its basically ATX using AT style cabling.

Seeing that single 6 pin connector to me just means to double check the power supply that it isnt a dell oem unit.

I have a couple power supplies that have that connector and are standard ATX pinouts but since dell used those to supply 3.3v to their motherboards instead of pinning their 20 pin using the ATX standard to me that connector is a warning sign to check my psu wiring.

Actually that goes for motherboards as well although besides dell motherboards I have only seen the 6 pin connector on my server motherboards and most of them use the standard ATX pinouts.

If we're talking about ATX PSUs with AUX connector I remember Codegen brand (from early P4 period- typically 300W).
If we are at motherboards, then surely Jetway P4XFBU or P4XFCU

Deano wrote on 2024-03-31, 06:32:

Also worth mentioning some ATish (late LPX) motherboards have 3 Px connectors.

Just before the ATX standard appeared Intel provided a new standard for its Pentium Pro LPX platform, it didn't take off but it provides soft On (no external power switch), idle power and a 3rd Px connector for a 3.3v rail.

Its basically ATX using AT style cabling.

I've seen some late socket 7 Acer built machines with that kind of mess too.

Grem Five wrote on 2024-03-31, 11:15:

Seeing that single 6 pin connector to me just means to double check the power supply that it isnt a dell oem unit.

I have a couple power supplies that have that connector and are standard ATX pinouts but since dell used those to supply 3.3v to their motherboards instead of pinning their 20 pin using the ATX standard to me that connector is a warning sign to check my psu wiring.

Actually that goes for motherboards as well although besides dell motherboards I have only seen the 6 pin connector on my server motherboards and most of them use the standard ATX pinouts.

I've definitely seen very early P4 motherboards with the AUX connector that were not for Dell machines.

Aux was used on some early server/workstation motherboards before 12V P4 connector became a standard.

kingcake wrote on 2024-03-31, 17:19:

Grem Five wrote on 2024-03-31, 11:15:

Seeing that single 6 pin connector to me just means to double check the power supply that it isnt a dell oem unit.

I have a couple power supplies that have that connector and are standard ATX pinouts but since dell used those to supply 3.3v to their motherboards instead of pinning their 20 pin using the ATX standard to me that connector is a warning sign to check my psu wiring.

Actually that goes for motherboards as well although besides dell motherboards I have only seen the 6 pin connector on my server motherboards and most of them use the standard ATX pinouts.

I've definitely seen very early P4 motherboards with the AUX connector that were not for Dell machines.

Yes both of the PSUs I have with this AUX connector are roughly P4 era. An Antec one and a Turbo Link brand one. Both are new old stock, and both were tested prior to use with a PSU tester. They seem to work fine, I was just curious what this connector was. I had never seen one before acquiring these. It's also difficult to figure out what it is without knowing that it's specifically called a "6 pin aux" connector.

Here's an example of a P4 motherboard I have with the AUX connector:

It's definitely the standard ATX one, not the proprietary Dell connector.

Here's something more important to note: if the PSU has a 6-pin Aux. connector, it's probably old enough that the caps inside it should be checked - visually, at the very least.

AbsolutelyFree wrote on 2024-04-02, 08:31:

Yes both of the PSUs I have with this AUX connector are roughly P4 era. An Antec one and a Turbo Link brand one. Both are new old stock, and both were tested prior to use with a PSU tester.

Ah, TurboLink... 🤣
It's a "brand" that re-brands typically the lowest-tier (garbage) PSUs from other manufacturers. Never seen a good one worth keeping... that is, unless you like to play with electronics / rebuilding PSUs like I do. Then these are kind of like a "sandbox" to try out with different (and better) parts to try to improve them. Here's a look at mine on badcaps.net

In short, I don't recommend to use this PSU in a computer - not in its stock form, at least.
I still do have mine and occasionally use it for powering DC motors and other such similar small electronics projects, where higher ripple and noise is not an issue.

That being said, the old Antec might just be another CWT unit and also in need of a recap. Many old Antec PSUs were this way. Best to open it and check it. Just because it passed the "test" on a cheap PSU "tester" means absolutely nothing. Those PSU "testers" put the absolute bare minimum load to make the PSU run, so any issues with the PSU (be it due to bad caps or something else) might not show up, unless it's something really severe. The worst is when you take one such "tested" PSU and then you start running into all kinds of "random" problems on a system not working correctly. I've gone through this more times than I care to remember, and it's always a hair-pulling experience... until you realize it was the PSU all along that was causing the issue.
So when it comes to old PSUs: open and check for bad / bulging caps and don't just trust a PSU "tester".

momaka wrote on 2024-04-02, 13:27:

...

Thanks for the heads up, I will be investigating these PSUs further soon.