I have SSD drive, on which Win 8.1 is installed, and booted from.
I also have 3 other HDDs connected, not RAID or something.
I have removed one of them, and after next start PC turned off unexpectedly during Windows startup process. I mean, were already was Windows logo on screen.
Then tried and removed another HDD (putting previous one back) ... same result.
Then I put back all HDDs to their place - Windows started up correctly (allowing me to write this now).

What... What is this?


In the end, it's failed PSU. I don't know how is this all related, but I replaced my current one, with older PSU I had, and all worked miraculously.

1 Answer 1


Sounds like it's a BIOS "feature" <- yes, air quotes

A typical Windows 7/8.x install will normally have your boot disk in AHCI mode. Based on what you are saying, the action of removing one drive is causing your BIOS to switch to IDE mode as a precaution because it recognized that a disk was removed.

This is an issue because the registry setting in your OS probably says "Operate in AHCI"

The solution:

Before removing the disk, verify in which SATA mode your SSD is running.

After removing the disk, make sure to go into your BIOS and check the SATA mode for your boot drive.

Let me know how it goes.

Good luck!

Update 1

A few more things to try:

  1. Within Windows, before removing the HDD, open your Disk Management Console and set the drive to "Offline".

enter image description here

  1. After removing the HDD, go into your BIOS and try disabling the SATA port on which the HDD used to be connected to.

  2. Remove the SATA cable from the port on the motherboard before starting the computer (I'm just grasping at straws with this suggestion)

You may use all of these suggestions at one time or try them out one-by-one.

Let me know how it goes!

Update 2

Looks like a true motherboard or BIOS issue.

  • Thanks for fast reply. I checked, before removal it was AHCI. After removal, i went into BOOT and it still was AHCI, I did let Windows try and boot, but it failed.
    – David
    May 6, 2015 at 16:38
  • @David Thanks for the update. I will update my answer with more suggestions shortly.
    – MonkeyZeus
    May 6, 2015 at 17:25
  • @David I've updated my answer
    – MonkeyZeus
    May 6, 2015 at 17:32
  • Not working as well. Funny note (or not funny). I've created bootable USB, PC shuts down as well, when I try to boot from said USB. I will now try to create bootable linux based USB, and see if it all issue with Windows and not MB.
    – David
    May 8, 2015 at 12:40
  • I now think that quotes around "issue" needs to be removed. 1) made Ubuntu USB stick. 2) Turned off SATA controller in BIOS setup. 3) Disconnected every SATA cable from MB. ... PC turns off when loading from Stick. PC stays on in BOOT setup. PC works when all HDDs/SSD are connected.
    – David
    May 8, 2015 at 14:05

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