So, I installed a new hard drive on my friend's computer, and used a disk cloning tool to copy the contents of his original drive (Hitachi 1TB, will be referenced from now on as /sda) to a new one (Toshiba 3TB, will be referenced from now on as /sdb). After the disk clone was done, I booted to /sdb, and it works fine, but I soon learned that I could only format 2TB of it, and no more, and had to just boot from /sda, and use /sdb as storage. (I hear that UEFI is a requirement for >2TB boot disks, and his motherboard doesn't feature it) At this point, I set the BIOS to give /sda priority over /sdb, and I boot it up. Upon booting, the OS starts installing some drivers of some sort. I believe the OS called it "Generic Volume", or something along those lines, and I was forced to reboot after they were done installing. After rebooting, I notice that /sdb is now the C: volume, even though I was supposed to have booted from /sda. Thinking that somehow the BIOS booted /sdb rather than /sda, I turn off the computer, unplug /sdb, and reboot. After the POST, Windows gives me a boot error before the Windows logo shows up. (At the bootloader) I can retrieve the specific error in a couple of minutes to reboot and read it again.