A Permanent Solution to the Dell 'Fake ATX' Power Supply Problem?

rick12373 wrote on 2025-03-20, 18:51:

I was thinking about trying to get a new PSU for the Dell Dimension L866R I have. The power button is connected to the motherboard and it has an ATX connector and an AT connector. Is it possible to get a new PSU like this? Here is a picture.

Unless the power supply is failing to work, it's best to leave it as-is. That extra blue & black wires cable is actually the 3.3v power lines and the 'ATX connector' is actually a custom pinout that Dell used during that era: Re: A Permanent Solution to the Dell 'Fake ATX' Power Supply Problem?

It's a fair bit of work to change over to actual standard ATX pinout, but I can see your board has the shifted holes on the PCB where the regular ATX connector goes compared to where the Dell ATX connector goes.
The Dell ATX > ATX connector adapter cables aren't available anymore so there's not an easy solution to installing an ATX power supply with that mainboard.

Sounds reasonable. It is working fine at the moment.