Every other time my PC won't boot into Windows 10

[LoneWolf121188]

I think it's a mobo issue because this only happened after updating my BIOS. However, when I boot up my PC from a cold shutdown, it POSTs, then goes straight to a black screen. The HDD activity light is flashing rapidly, but nothing happens. I've left it there for minutes and it does the same thing. Then I hit the restart button on my case and it boots up into Windows (10, in UEFI mode) just fine. This happens consistently, regardless of if I have any external USB hard drives or flash drives connected.

In my BIOS, I have CSM disabled and the only option under my boot priorities is the Windows Boot Manager.

Any ideas what's going on?

 

[wingman99]

Did you try going back to your old Bios that was working fine?

 

[JrClocker]

I had this happen on my motherboard when I had "fast boot" enabled. Random stuff like this.

Once I turned off fast boot in the bios, everything was fine.

 

[LoneWolf121188]

Did you try going back to your old Bios that was working fine?

Don't know why I didn't think of that...I'll try it, thanks!

I had this happen on my motherboard when I had "fast boot" enabled. Random stuff like this.

Once I turned off fast boot in the bios, everything was fine.

Tried it, no dice.

 

[Pepi93]

Did you do an upgrade or fresh clean install?

If upgrade, did you install proper chipset and other mobo drivers for win10?

Same with GPU, Audio driver etc...but chipset is the main concern...

 

[LoneWolf121188]

So I figured it out: turning CSM back on, then setting all the boot options to UEFI only fixed the problem. Must be a bug in this latest BIOS, since I had CSM disabled in all previous BIOS versions. Weird.