I am trying to upload an operating system onto a new pre-built computer. I downloaded Windows 7 ISO, then put it into Rufus in order to put it onto a USB-FD. I changed the PC's BIOS to startup from the USB drive. Once the USB-FD was inserted, the screen went black and stated "loading operating system", but it has never left this screen. I tried pressing F8 and F12, but to no avail. Are there any troubleshooting suggestions? I have never done ANYTHING like this before and I found myself way over my head, but with all the information that I've found on this forum so far that I keep on trucking, so thank you, community.