Computer says No bootable device?

I recommend this video https://www.youtube.com/watch?v=B4nVdq2n...

I've faced this issue before and I tried know 4 different methods. There are several reasons that can cause this error. I cant explain every step in detail but I think anyone who is facing this issue would be able to understand or you can read this article: Fix No Bootable Device Error (Thoroughly explained)

One of the following step will sort out the problem:

1. Are you using a tool to make your removable device bootable? If not, then create a bootable Windows 7 USB device via Rufus.

2. Restore the Operating System

3.Using following CMD Prompt:

bootrec /fixmbr

bootrec /fixboot

bootrec /scans

bootrec /rebuildbcd

4.Re-Install or Reset Windows

Either your lucky and a wire is loose, (power, or ide/sata) at drive or mother board. Or the more likely. Dead hard drive. This happens more often then you'd think. Drive may still spin up and make noise also, it just doesn't access data any more. You can usually tell this when it makes a repeated pattern of clicks. This is the drive head trying to find it's starting point to put it plainly. Anyway, unfortunately , if it's the later you need a new boot drive and a Windows restore disk. You can use about any size drive you want, this is where people often use smaller SSD drive for fast boot and add another slower but Huge data drive for media. You can usually get a system restore disk from the manufacturer of your computer. If not available there are instructions to how to create one on the windows website, using another computer to create a bootable USB that will load everything needed to your new hard drive. Hope this helps.