https://rog.asus.com/forum/showthread.php?110058-Z390-I-Random-reboots-under-load
Wow, so close to your complaint and model. I see SPECCY is NOT REPORTING THE RAM correctly as well as the SPID chip on the RAM. This could be out of date, buggy bios or drivers. I do not have a tool to check your driver versions but Asus will work that and the BIOS.
-> You didn't make it clear if this is a clean Windows install. Changing motherboards and more does require a fresh install which folk want to debate about. (I don't!)
Also there's some issue with the Seagate in this report which has been written up over and over and is known to cause reboots, hangs and more. Look at the way over the top numbers in 01 and 07. In short the drive has not failed but would never be used on a performance or "stable" PC.

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