1. Flash new BIOS Firmware, if there is some
2. Reset mainboard (better via jumper, not reset option in BIOS)
3. Reseat the RAM modules, try booting with only 1 or 2, see if that makes a difference (your HW looks new, so not impossible, but unlikely that one module is broken)
4. Switch off everything you find with powersaving in the BIOS, especially ASPM
5. Try boot without any USB device plugged in
6. Look in BIOS if you can change USB controller modes betwenn 3.0, 3.1 or 3.2
7. Change the slots of the pci-e cards or try to boot without them for test, see if the error disappears
8. Double-check sata cables, they’re sometimes wobbly and moving the server could do the rest.
9. Is your PSU new or already older? PSUs are ageing and/or if an older (but still okayish PSU) should drive a newer CPU it could provoke a brown-out, because they cannot deliver the fast load changes actual CPUs need.
Tutorial for Cloud VDS
