Before doing anything, i would advise to make a complete separate and verified backup of your data if they are important of course.
Steps to try:
If you have got an additional spare and brand new drive, you can try something.
Connect the spare drive to the system, note down the model and serial no in order to identify it later.
Go into Intel Matrix Storage Manager.
Make sure to format it and make it online from Disk Management.
From IMSM, right click on the new drive and mark it as spare.
Restart the system.
It should start the rebuilding automatically.
Once rebuilt has been completed, identify each drive by activating the LED port from IMSM.
Remove the failed drive and test it on another system.
Use the manufacturer tool to test the drive.
If drive is ok, format it and use it as a hot spare or mark it as non-raid to store data.
I have attached some pictures for you below.
All the best,
Thank You for the reply. We had to redeploy the server because of the time it was taking to research this problem. I did not want to randomly switch drives trying to find out IF one was bad as this could have had an affect on the data. As I said in the original question, NONE of the drives show as bad in Matrix Storage Manager (BIOS or the program that runs in Windows). The system just started booting into Windows again. We believe the motherboard may be at fault.
The server is set to be replaced in early summer.