Seems like a bad hard disk. Can happen.
Clone your current hard disk to a new one (or an SSD if not too big), then replace it with the new one. Might help, unless the old one is so damaged already that it can't be copied.
If it can't be copied, you have to reinstall Windows, reinstall all your programs and see what data that you forgot to backup you can still read from the old disk.
Alright, so a while ago i left my home for the summer and therefore i didn't use my PC for about 2-3 months. It worked perfectly fine before i left, but when i came back and attempted to boot it up, the issues started.
When i attempted to turn the PC on and it got past the Intel screen, a few possible things could happen:
1. it took me to a black screen with white text in the upper left corner that said:
"A bootable device has not been detected.
Please refer to the product guide at
http://support.intel.com/support/motherboards/desktop"
2. the same as 1., but this time the text said:
"No bootable device -- insert boot disk and press any key"
3. it would actually boot up normally and work, but from time to time, some of the programs that are running would freeze and stop responding for a few minutes (usually 2-5 mins, rarely longer) and sometimes even windows itself started acting a bit strange (the taskbar stopped responding and sort of "reloaded", the windows start screen stopped responding for a bit...etc)
Recently it seems to have gotten worse though. For the past few days, every time i tried to boot it up, the same "no bootable" device things happened but when it actually manages to get past that and get to the windows loading screen, it stays there for longer than usual and eventually results in a blue-screen, which would either cause a reboot or a freeze on said screen until i turned it off
What exactly is the problem here and what can i do about it?
(also i'm sorry for any grammatical/spelling errors, english isn't my native language )

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