PC won't detect spinning internal hdd, and powering off

[Poororo]

Ok, now I'm really worried, so PC won't detect spinning internal hdd (details at my post on the bsod section (I'm very sorry I'm new to the forum and I'm using the app)) and when I power it on and press f2 for bios, after a few seconds, it shuts down and I have to power it on again

Need help

 

[AddRAM]

Your computer shuts down when you try to get to the bios ?

Are you sure F2 is the correct key ?

What happens if you don`t hit any keys ?

Does the computer still shut down ?

 

[Poororo]

It randomly powers of when i(even if I don't) enter bios