Asrock X79 Extreme6 Endless Install Loop

If we skip, that maybe the replacement board is damaged, this is what I would do.
Check if CPU temperature is okay, so it is not a cooler problem.
Don't connect any SATA or USB cardreader, the system should run into UEFI, by itself.
Also use only 1 memory module
maybe reflash the BIOS
https://download.asrock.com/BIOS/2011/X79%20Extreme6(3.10)ROM.zip
Or buy a new BIOS chip with 3.10 on it.
Create a bootable USB stick with Rufus and Ubuntu Linux on it, start and go with f11 in the bootmenu, and run Ubuntu from the USB stick.
If that works, it could be OS related.
Try installing Windows 7, to see if that works.
When that works, I would say the board itself, is okay.
You could try an upgrade from Windows 7 to Windows 10, to see if that also works.
If yes, a clean installation should work, but in GPT mode.

marccunn wrote: I am not clear about this instruction you gave: "Don't connect any SATA or USB cardreader, the system should run into UEFI, by itself."

If you do not have any bootable devices connected to the system (no hard disks, flash drives etc)
then the system will automatically enter the UEFI (BIOS) on boot.

Hello all, here is an update of my progress thus far....

Unfortunately, I am sorry to say there is no progress.

I am still stuck with an endlessly repetitive installation loop, as follows....

The X79 Extreme6 installation begins the POST process after I push the start button on the front of the Lian-Li PC-60USB case.

Dr. Debug cycles through the sequence of useless codes.

At "A2" the Dr. Debug LEDs go out, presumably handing off the installation sequence to Windows 10 Pro x64.

The monitor goes blank for a few seconds.

Then the trapezoidal blue 4-pane Windows logo window appears.

After a few seconds, the circle of little white balls appears and the little white balls begin to spin around.

Then sometime within the next minute, the Extreme6 shuts itself down, and then within 10-20 seconds, it wakes itself up and begins the installation process all over again.

That is still exactly what happens each time, without variation....

I should say here that I have always been able to use the F2 and/or Del keys to get into the BIOS to change settings during POST.

Also I have always been able to use the F6 key to get into the BIOS Instant Flash utility during POST.

So far, I have attempted approximately 40 clean installs, and the results are always exactly the same as described above.

Here are the steps I have taken so far.

I bought 8 new 8Gb sticks of compatible Crucial RAM.

I ran MEMTEST, to test those RAM sticks on the Extreme6, and MEMTEST did not find any errors after running continuously for about 48 hours.

I have tried installing W10 Pro x64 from a USB stick, with one stick of RAM in the A1 slot. Exact same result as above.

I have tried installing W10 Pro x64 from a USB stick, with 2 sticks of RAM (in the proper slots recommended in the Extreme6 manual). Exact same result as above.

I have tried installing W10 Pro x64 from a USB stick, with 4 sticks of RAM (in the proper slots recommended in the Extreme6 manual). Exact same result as above.

I have tried installing W10 Pro x64 from a USB stick, with 8 sticks of RAM (in the proper slots recommended in the Extreme6 manual). Exact same result as above.

I bought a new USB stick, thinking the USB stick I had been using might be damaged, and repeated all installations with all the memory stick configurations noted above. Exact same results as above.

I then tried installations as noted above consecutively with the USB stick moved each time to each of the USB2 and USB3 connectors on the rear panel. Exact same results as above.

I then created a USB installation disk using RUFUS, and used it to try the all the various installations in the various configurations as noted above. Exact same results as above.

I then installed a DVD drive, and tried an installation using one of my old W10 Pro x64 disks. Exact same results as above.

I also tried an installation using one of my old Windows 8.1 Pro x64 disks. Exact same results as above.

I also tried an installation using my old Windows 7 Ultimate x64 disk. Even though there were only 4 little balls - colored red, blue, yellow and green, rather than little white balls - spinning around, the results were exactly the same as above.

I have also tried reflashing the BIOS with both vL2.45 and v3.10, and then repeating all the configurations noted above for each BIOS version. Exact same results as above.

I have tried every BIOS setting boot option I could think of. Exact same results as above.

I have tried 4 different clean Samsung SSDs. Exact same results as above.

So always the results were exactly the same...once the little white (or colored) balls start to spin, the Extreme6 shuts down within a minute and then restarts on its own.

If I have missed anything in the instructions from Xaltar and threadzipper1957, please let me know.

I have also contacted the Ebay seller, whose posting indicated that the X79 Extreme6 had been tested and worked perfectly, to let them know about this endless installation loop issue, and to ask them if they might have any insight into this issue. No response yet.

If you have any further options for me try, please let me know.

Thank you all for all your advice thus far!