No USB boot option in BIOS/0x000000f boot error

[Catishcat]

I don't know why, but when I turn my Noname PSU off, Windows 10 is not booting. It started only when I upgraded to Windows 10. I always get an error 0x000000f, saying that BOOT\BCD is dead. I solved that problem 3 times with Windows 10 installer on my USB drive, but now it does not even show up in boot options! I downloaded it from Microsoft's website, with Media Creation Tool. I will try replacing the battery today, but it still will not boot. Other three times problem was solved only by accessing recover option in installer, going to console and typing there "c:" and "dir"... And after next restart it boots normaly o_o

My useful PC specs (I mean random error generator) are:

MB: ASUS P5KC
HDD: Noname 200GB drive (C: D: ) and WD Blue 1TB (E: F: G: )
USB Drive: Noname 16GB drive

1. Why is this happening when I turn off my PC?
2. Why solution to this problem is so... strange?... ?
3. Why USB boot option does not appear this time?

 

[Lutfij]

1| The error code 0x000000f pertains to HDD error judging by your HDD capacity and the brand I'd say its on its way out due to regular wear and tear. Upto the point that it is invisible during BIOS' boot option.
2| The point you made about your no name PSU has also put benefit in doubt that the system may have suffered from electrical damage receiving dirty power from the unit.
3| Your motherboard may also be showing signs of BIOS corruption or that the CMOS battery is giving out as well.
4| Everything about your motherboard screams full support for Windows 10 as it has drivers available upto Windows 8.1 which in turn can be run in compatibility mode.

If you could source a proper(new) HDD as your boot device, I'm sure the errors and BIOS will go away.

My 2 cents though.

 

[Catishcat]

I solved it by downgrading to Win7. That's the only solution.