Question Disabling CSM reboots back to BIOS

Metalrocks

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Nov 13, 2014
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I hope this is the right place to ask. Wasn't sure if this was an win 11 one or hardware.

I have a AsRock B365M phantom gaming 4 motherboard and like to install win 11.
What I currently have is 10 on a HDD. Obviously HDD isn't really that good anymore so I like to remove the HDD and built in an M.2 drive to install 11 on it. So in short, remove the HDD with 10 on it and exchange it with an M.2 where I like to install 11 on it. Like a fresh start so to speak.

Now, I know I need to have TPM and secure boot enabled. I have done this, but according to the Windows Healthcheck, I still do not meet requirements for 11 due to CSM. I went into BIOS and disabled it, but now it only goes straight into BIOS. No matter what I do. Once I enable it, computer starts up normally.

I did look up the issue and saw few workarounds, but since I'm going to replace the drive, is my computer able to startup and install 11 once I disable CSM?
 
Its likely that your current install is set up as MBR and it can't boot without CSM.

If you install WIn 11 on PC, with csm disabled, you won't have this problem as it will use UEFI

see spoiler for explanation
Explanation of terms:

UEFI - Unified extensible Firmware Interface
If your PC is less than 11 years old, you have a UEFI bios now


In 2006 or so Intel decided the bios as it was at time was too limited and needed to be replaced so that it supported newer technologies as they were invented

By about 2009 a consortium of hardware makers had combined to create UEFI standard


Old bios were limited, they didn't know what a mouse was for, so everything was keyboard driven
they weren't expandable, everything had to fit in a small amount of memory
they only supported Master Boot Record (MBR) which can only have 4 partitions per drive (there are tricks to get around this) and max drive size is 2.2 tb

UEFI bios overcame all the limitations of legacy bios (as it came to be called)
it supports mouse, it has a GUI so it looks better than previous bios could
Its expandable, it can be added to to grow as new hardware is created.
UEFI supports MBR & GPT Drives


GPT = GUID Partition Table
GUID = Global Unique ID = Every GPT drive on earth has a unique ID
GPT drives can have a max of 255 partitions on them
Max size of a GPT drive/partition is 18.8 million TB

CSM stands for compatibility support module - it emulates the old bios type and can only boot MBR drives
UEFI can recognise both MBR & GPT. its backwards compatible.

Win 10 & 11 have both preferred GPT as drive format.
 
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Its likely that your current install is set up as MBR and it can't boot without CSM.

If you install WIn 11 on PC, with csm disabled, you won't have this problem as it will use UEFI

see spoiler for explanation
Explanation of terms:

UEFI - Unified extensible Firmware Interface
If your PC is less than 11 years old, you have a UEFI bios now


In 2006 or so Intel decided the bios as it was at time was too limited and needed to be replaced so that it supported newer technologies as they were invented

By about 2009 a consortium of hardware makers had combined to create UEFI standard


Old bios were limited, they didn't know what a mouse was for, so everything was keyboard driven
they weren't expandable, everything had to fit in a small amount of memory
they only supported Master Boot Record (MBR) which can only have 4 partitions per drive (there are tricks to get around this) and max drive size is 2.2 tb

UEFI bios overcame all the limitations of legacy bios (as it came to be called)
it supports mouse, it has a GUI so it looks better than previous bios could
Its expandable, it can be added to to grow as new hardware is created.
UEFI supports MBR & GPT Drives


GPT = GUID Partition Table
GUID = Global Unique ID = Every GPT drive on earth has a unique ID
GPT drives can have a max of 255 partitions on them
Max size of a GPT drive/partition is 18.8 million TB

CSM stands for compatibility support module - it emulates the old bios type and can only boot MBR drives
UEFI can recognise both MBR & GPT. its backwards compatible.

Win 10 & 11 have both preferred GPT as drive format.
Didn't know that part. Interesting

So i can disable CSM first before I take out HDD and install the M.2. Or I should be able to access BIOS after I install the new drive.

BTW, should I remove my other 2 drives before installing win 11?
 
There should only be ONE, repeat ONE, drive connected when yo do this OS install.

This has been outlined in the install tutorials you've already been shown.
Apologies, I wasn't clear with my statement.

I have 3 drives in total. one HDD and two SSD's. As mentioned, the HDD contains the OS. Which I like to take out now and replace it with a M.2 to have 11 on it.
 
Apologies, I wasn't clear with my statement.

I have 3 drives in total. one HDD and two SSD's. As mentioned, the HDD contains the OS. Which I like to take out now and replace it with a M.2 to have 11 on it.
All drives, including and especially the HDD with its existing OS....need to be disconnected when you install Win 11 on this M.2 drive.

Let me repeat that...ALL drives, except the M.2...physically disconnected.