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CSM disabled to UEFI then no boot drive found

CSM disabled to UEFI then no boot drive found
« on: December 23, 2021, 06:15:27 pm »
I have an B550 Aorus Pro AC motherboard (new bios F14e) with a Ryzen 5600x processor and a Nvme 4.0 system drive running Win10.
Bios mode is currently Legacy and I would like to change to UEFI for Win11 compatability.
In Bios setup if I change CSM to "disabled" my computer will not boot.
No bootable disk drives are available to assign in the Boot Option Priorities Menu, however all drives are connected in Plug In Devices Sytem Info.
The system Nvme boot drive is NTFS formatted with GPT partitions.
Any suggestions as to the problem?
Thanks

shadowsports

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Re: CSM disabled to UEFI then no boot drive found
« Reply #1 on: December 23, 2021, 10:02:29 pm »
Greetings,
For NVMe, either port M2A_ or M2B_ can be used
UEFI boot requires a GPT format - you said your disk had this formatting

What SATA operate mode were you using? AHCI or RAID

Boot Option Priorities
#1 - select your NVMe in whichever slot its installed in

If you have Fast or Ultra Fast Boot enabled - Disable it

CSM Support - [Disabled]

Secure Boot - [Enabled]

If the settings above do not allow you to select your m.2 as a boot drive, please provide you full system specs including all connected devices, add on cards, etc. 

Z390 AORUS PRO (F10) \850w, 9900K, 32GB GSkill TriZ RGB - 16-18-18-38, RTX 3080Ti FTW3 Ultra, 960 Pro_m.2, W10 21H2
Z370-HD3P (F5) \750w, 8350K, 8GB LPX 3200 - 16-18-18-38, GTX 970 FTW SC, Intel SSD, 2TB RAID1, W10 21H2
Z97X-UD5H \850w, 4790K, 32GB Vengeance, RTX 2080 FTW

Re: CSM disabled to UEFI then no boot drive found
« Reply #2 on: December 26, 2021, 07:33:08 pm »
Configuration that boots:

NVMe installed in port M2A_CPU
NVMe is GPT format NTFS
SATA mode AHCI with RAID mode [Disabled]
Memory XMP profile enabled 3600Mhz
Boot Option Priority #1 NVMe
Fast or Ultra Fast Boot [Disabled]
CSM Support - [Enabled]
Secure Boot - [Disabled]

Full system specs:
AMD Ryzen 5600X (not overclocked - BIOS in Auto mode)
Gigabyte B550 Aorus Pro AC
BIOS F14e
16 Gb (2X8Gb) HyperX Fury DDR4 PC-4 28800 3600 Mhz (HX436C17FB3AK2/16)
NvMe 4.0X4 ADATA GAMMIX S50 1Tb m.2(2280) (AGAMMIXS50-ITT-C)
SSD Toshiba TR-150 (480Gb) SATA 6Gb/s Backup Disk
HD WesternDigital WD1002FBYS SATA 3Gb/s Backup Disk
EVGA GeForce GTX1060 SC ACX2.03Gb in PCI 3.0X16 slot

Setting CSM support to [Disabled] results in "No bootable drive found"

Re: CSM disabled to UEFI then no boot drive found
« Reply #3 on: December 27, 2021, 11:07:23 am »
I suspect that the boot manager is pointing to SSD [Disk 0] instead of NvMe System Disk C: [Disk 2]
The PC is a home build which I upgraded to a new motherboard with a new NvMe drive and memory.
In the process I migrated the Win10 installation from the old SSD drive to the NvMe drive with no problem and left it attached as a backup.
However now when I remove the old SSD [Disk 0] the system will not boot even with CSM [Enabled]

I ran the command C:\Windows\system32>bcdedit

Windows Boot Manager
--------------------
identifier              {bootmgr}
device                  partition=\Device\HarddiskVolume1
description             Windows Boot Manager
locale                  en-us
inherit                 {globalsettings}
default                 {current}
resumeobject            {9093c612-543f-11eb-9d78-f8ac65ab36a9}
displayorder            {current}
toolsdisplayorder       {memdiag}
timeout                 30

Windows Boot Loader
-------------------
identifier              {current}
device                  partition=C:
path                    \Windows\system32\winload.exe
description             Windows 10
locale                  en-us
inherit                 {bootloadersettings}
allowedinmemorysettings 0x15000075
osdevice                partition=C:
systemroot              \Windows
resumeobject            {9093c612-543f-11eb-9d78-f8ac65ab36a9}
nx                      OptIn
bootmenupolicy          Standard

Is this OK? it seems to point to C:/ drive...

Attached is Disk Management Screenshot

shadowsports

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Re: CSM disabled to UEFI then no boot drive found
« Reply #4 on: December 27, 2021, 04:43:40 pm »
Greetings,
You are correct about the Boot Configuration Data.  As you can see, my BCD is different from yours.  You are missing the UEFI path.

I suspect your migration is what has led to your current situation.  What did you use to convert the existing install to GPT?  Did you clone, or actually migrate?  There is a difference.  It looks like you cloned your existing install. 

Leaving the former boot drive attached.  This is never a good idea, in fact, when you do use this method, the disk you are cloning to (destination) should be installed in place of the current boot drive (source) prior to the clone operation. This avoids the incorrect BCD above.  After the clone, the source disk should be removed or disconnected before booting into the OS for the first time.     

My BCD for reference: 
 
C:\WINDOWS\system32>bcdedit

Windows Boot Manager
--------------------
identifier              {bootmgr}
device                  partition=\Device\HarddiskVolume4
path                    \EFI\MICROSOFT\BOOT\BOOTMGFW.EFI
description             Windows Boot Manager
locale                  en-US
inherit                 {globalsettings}
default                 {current}
resumeobject            {2f3c1b92-1ebb-11eb-b07a-cdaf4537ddef}
displayorder            {current}
toolsdisplayorder       {memdiag}
timeout                 30

Windows Boot Loader
-------------------
identifier              {current}
device                  partition=C:
path                    \WINDOWS\system32\winload.efi
description             Windows 10
locale                  en-US
inherit                 {bootloadersettings}
recoverysequence        {2f3c1b94-1ebb-11eb-b07a-cdaf4537ddef}
displaymessageoverride  SystemRestore
recoveryenabled         Yes
isolatedcontext         Yes
allowedinmemorysettings 0x15000075
osdevice                partition=C:
systemroot              \WINDOWS
resumeobject            {2f3c1b92-1ebb-11eb-b07a-cdaf4537ddef}
nx                      OptIn
bootmenupolicy          Standard

C:\WINDOWS\system32>

My Disk Management for Reference:


I think you should be able to fix this.

You'll need windows 10 boot media. 

Disconnect the old boot drive
Start the system and enter BIOS
Make your changes discussed above

Insert your windows 10 boot media
Use F10 in BIOS to save and Exit
On restart use F12 to select one time boot device
Select path to your W10 install media
Select Repair or the Recovery Environment
Select Command Prompt
At the prompt type >bootrec /rebuildbcd
Select your windows installation to add and press Y

Exit and restart.  This should allow the system to boot.  Let us know how it goes.

Use the following for reference:
https://www.thewindowsclub.com/rebuild-bcd-windows-10
https://www.thewindowsclub.com/how-to-repair-the-efi-bootloader-in-windows





« Last Edit: December 27, 2021, 04:45:06 pm by shadowsports »
Z390 AORUS PRO (F10) \850w, 9900K, 32GB GSkill TriZ RGB - 16-18-18-38, RTX 3080Ti FTW3 Ultra, 960 Pro_m.2, W10 21H2
Z370-HD3P (F5) \750w, 8350K, 8GB LPX 3200 - 16-18-18-38, GTX 970 FTW SC, Intel SSD, 2TB RAID1, W10 21H2
Z97X-UD5H \850w, 4790K, 32GB Vengeance, RTX 2080 FTW

Re: CSM disabled to UEFI then no boot drive found
« Reply #5 on: December 28, 2021, 10:52:35 am »
I tried to follow your procedure but encountered an error in the Repair Environment when running bootrec /rebuildbcd
My windows installation was listed as e:/windows but when I pressed [Y] I got the error "drive could not be found"
So I entered the command bcdboot e:/windows /s c: which worked
Now the computer boots fine in UEFI mode and SecureBoot but there are no entries in bootloader!!!
Now the only Boot Sequence option in BIOS is: Windows Boot Manager [P1:WDC1002FBYS] which is the backup disk 0 [F:]
My guess is that I messed up the drive letters and this can be repaired with the bcdboot command???
« Last Edit: December 28, 2021, 11:37:53 am by aldodis@otenet.gr »

shadowsports

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Re: CSM disabled to UEFI then no boot drive found
« Reply #6 on: December 28, 2021, 02:37:45 pm »
Greetings,
That sounds correct.  Refer to the 2nd link above for examples.  You are making progress. 8)
Z390 AORUS PRO (F10) \850w, 9900K, 32GB GSkill TriZ RGB - 16-18-18-38, RTX 3080Ti FTW3 Ultra, 960 Pro_m.2, W10 21H2
Z370-HD3P (F5) \750w, 8350K, 8GB LPX 3200 - 16-18-18-38, GTX 970 FTW SC, Intel SSD, 2TB RAID1, W10 21H2
Z97X-UD5H \850w, 4790K, 32GB Vengeance, RTX 2080 FTW

Re: CSM disabled to UEFI then no boot drive found
« Reply #7 on: December 28, 2021, 06:08:08 pm »
Many thanks for your kind help, I managed to clean up my system by creating a new EFI partition and used bcdboot as per the attached screenshot of commands.
I checked that my computer boots very quickly with the Backup HDD F: drive detached.
I renamed the [EFI] folder on F: to [Backup EFI] so it would not be a second option found by the BIOS boot manager
When I reattach the F: and reboot the boot process seems to be hunt around the HDD for some seconds which bugs me, why is this happening?

shadowsports

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Re: CSM disabled to UEFI then no boot drive found
« Reply #8 on: December 31, 2021, 02:28:05 pm »
Greetings,
If you remove this disk from the system, does it boot faster?

HD WesternDigital WD1002FBYS SATA 3Gb/s Backup Disk

I looked at the model.  This is a WD raid edition disk.  Mechanical drives add seconds to boot time plain and simple.

In addition, WD does not recommend using RE disks as standalone drives.  They have a separate TLER algorithm designed for RAID.  It will work, but will always be a little slower than a non RE disk. Its also SATA 3 which could in theory slow the system bus down. 

 
Z390 AORUS PRO (F10) \850w, 9900K, 32GB GSkill TriZ RGB - 16-18-18-38, RTX 3080Ti FTW3 Ultra, 960 Pro_m.2, W10 21H2
Z370-HD3P (F5) \750w, 8350K, 8GB LPX 3200 - 16-18-18-38, GTX 970 FTW SC, Intel SSD, 2TB RAID1, W10 21H2
Z97X-UD5H \850w, 4790K, 32GB Vengeance, RTX 2080 FTW