Connect the SSD only, and boot from the external USB windows 10 installation media. Use the repair option to correct the installation on the SSD. When finished verify you can now boot from the SSD without issues.     Next make sure only the old HDD is connected to the system when you perform these steps below. Make sure to disconnect all other drives, including the SSD. Make sure to mark the correct drive partition to remove!   Step 1. Insert the installation USB drive Windows 10 in your computer. Step 2. Reboot computer and boot Windows 10 USB installer. Step 3. Specify a language, a time, a currency, and a keyboard Step 3. Go to “Repair your computer” > “Troubleshoot” > “Advanced Options” > “Command Prompt”. Step 4. In Command Prompt, type “diskpart” and hit Enter to run Diskpart utiltiy. Step 4. Then, run these commands to delete the partition that you don’t need: list disk select disk n list partition select partition m delete partition  
Hello again! here's my original thread concerning getting a new M.2 up and running as a boot disk ... I did succeed.  [URL]#M50924  The machine originally had only a 1TB HDD. When that drive is disconnected, and both the new 1TB M.2 card and the new 2.5" 2TB SSD are installed, the machine boots just fine from the M.2 card. When I reconnect the original 3.5" HDD along with the other two drives, the machine boots only from the 3.5" HDD. I tried changing the order in BIOS but all I'm seeing are options like IV4P IV6P and Windows Boot Manager. I was hoping to see something like "boot from M.2 drive" etc. No changes I made in bios seemed to fix the issue. The 3.5" HDD does still have the original OS on it, I don't see how I can wipe it while the machine is running from it.   I don't NEED the extra 1TB of storage, but I alos don't like wasting perfectly good things either. Is there a way I can get all these drives to work in harmony, with the OS running from the M.2 drive?   Thanks again!
Aurora R8, new M.2 SSD, stop booting from the old HDD