A5: 500ms may be too short for usb port-power reset, Please refer to: https://github.com/raspberrypi/rpi-eeprom/issues/168
Q6: What to do if the X872 can't recognize the SSD or not working properly?
A6: a.First it is not recommend to use SAMSUNG SSD, as there will be EMC interference. Please replace with other SSD to test. b. Please try to close the WIFI to test.
==Matching Metal Case for X872==