Some more input: I have additionally installed the radxa sata top hat fan unit, with 4 Samsung 870 EVO satas. Additionally I use an USB2Ethernet adapter to make use of 2,5Gbit/s from WisDpi.
2 Power units with 12V/5A were used for test, a cheap one like the one from the post of asynch8 and an expensive one designed in Germany (huge weight difference and I expect more reliable power without the house burning down) as well as the Raspi power supply 5,1/5A connected, together and standalone (I guess nothing is destroyed refering to the Pmic).
When I connect to one of the 3 USB ports on the Raspi5 an USB-SSD 2,5" Samsung T7, the power is not enough to power the USB-SSD and without the USB-SSD the Ethernetadapter is sometimes stopping slowly its work from transfering 250 MB/s down to 0.
WITHOUT the Radxa Sata Top hat, at least I can power the USB-SSD, but not an other USB-HDD 2,5" (HDD is starting/stopping).
What I see, is, that the Radxa Penta sata hat is not deliverring enough power to the USB ports. Calculated the power of the power supply is more than enough for all units. Also the Raspi power adapter is not supporting the needed energy to the USB-ports.
An USB-Drive HDD 3,5" with own power supply is working fine at the USB-port.
Is there any design failure in the boards itself?