Make sure the ATX power supply is turning on. I think this may be accomplished using pin 14 on the 20-pin Molex connector. What I did was to install a full mATX motherboard PC and use that as a file server for the Pi computers. The Pi computers were then connected to USB2 hubs which I had modified to draw 5V directly from the connectors on the ATX power supply for powering hard disks and other accessories.Will try to get straight to the point. Refurbished a 1U case and installed a Flex ATX PS. Rated output is 5V at 12A. Purchased USB-C pigtails to connect ATX PS and 2X RPI 5. Only one RPI 5 installed with 32GB sd card and OEM heatsink/fan. RPi 5 works well with OEM PS. However, does not work with ATX PS. Missed that cable is only rated for 2A max. Appears that the pigtail only has 2 power pins. According to specs a HDD Molex connector should handle 11amps. Is there a USB-C cable that can supply 5+ amps?
Between the Pi and the ATX-powered USB hubs I chose the shortest 6 inch USB-C cables I could find. In the end a single ATX supply powered the PC and two HDs along with collection of twelve Pi 4Bs and four Pi Zero computers cooled by a wall of fans in a 2U server chassis.
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Oh, and also two 8-port gigabit switches powered from the same ATX supply.
In my experience under voltage can be a problem because of cable loss, increased resistance through corrosion and the fact that the ATX power supply may provide less than 5V. Note 5.1V is recommended.
Statistics: Posted by ejolson — Tue Apr 09, 2024 8:44 pm