PowerSpec G465 Unable To Boot to Windows

Welcome to the forum, DonnyG. I am sorry to hear you are having issues with your PowerSpec computer. I was able to locate your purchase via your forum email, I see that it's a PowerSpec G465. The "secure backup UEFI" error you are receiving is concerning. That implies that the backup EEPROM for the BIOS is trying to rewrite the main BIOS EEPROM from B (backup) to A (main). I haven't the slightest clue as to why it's attempting to do so unprovoked, especially on a brand new system.

Lets start by clearing caps and draining any residual power in the system. Start by unplugging the power cable from the unit and hold the power button down on the chassis for 60 seconds. Afterwards, release the power button and plug the power back into the power supply. Power the system back on, and tap the DEL key or F2 to enter BIOS. Assuming we can make it into BIOS, we can then force the system to load UEFI defaults, and try to proceed into Windows or your installation media. If this fails, and if you are comfortable doing so, unplug the power cable and remove one of the memory DIMM's. We can try a single DIMM in each memory slot to see if a module is DOA.

With the BSOD's being random, this is typically an indication that the memory or CPU's memory controller is having issues, but I do not want to draw that conclusion until we do additional troubleshooting to rule this out. With your distance from the store, I can absolutely understand the inconvenience of having to bring it back in, so I want to do our best to resolve this remotely if at all possible. Once you've confirmed the troubleshooting steps above, we can explore additional options. I look forward to hearing back from you.

EDIT:
I had an ASRock Z390 Phantom Gaming 6 around my bench to use as reference. Can you confirm if there are any debris or anything attached to the jumpers highlighted in red? There will be jumpers on the 9 pins below the highlighted pins, but nothing should be occupying the 6 that I highlighted. Also, highlighted in orange is the Debug panel. Can you tell me what debug codes you get?

Thank you for that information and for the quick response. Is it freezing on those codes specifically? Or simply cycling through them quickly? A2 references an issue with storage, however it's extremely common to see A2 flash quickly and go away as it initializes. 66 and 71 both pertain to chipset initialization. The code 99 is the most interesting, as that points somewhere to the PCIE subdomain. Meaning the graphics card or NVMe SSD is at fault, since both technically use PCIe lanes. Sadly it's difficult to troubleshoot the GPU as your system uses a Core i9-9900KF, which lacks integrated graphics. If you are comfortable doing so, we can attempt to swap the GPU to a different PCIe slot, which will rule out a failing slot. If you happen to have a spare PCIe GPU on hand, that would also be helpful to rule out the individual card.

In the meantime, I'll be sending you a private message to confirm your contact information. I'd like to forward that info to our Columbus management team to see if they can come up with a solution that will save you a trip to the store.