So after I replaced the screen on this laptop, i booted it up and came across a black screen that says:
Boot Device Not Found
Please install an operating system on your hard disk.
Hard Disk (3F0)
F2 System Diagnostics
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So I installed windows 7 and when I restarted the computer it went back to this. I've gotten it to occasionally boot up windows. I've done all the system diagnostics tests in F2 and they passed. I've done the hard disk test in the Bios menu and it passed. I don't know what to do.