[SOLVED] Can't install Windows 10 in UEFI mode, CSM disabled ?

[PEZ3000]

Hello!

I'm out of my depth in this area, I'm in the process of installing Windows 10 on a newely built computer with completely new parts:
Motherboard: Asus ROG Maximus XIII Hero
CPU: Intel Core i9-11900k
SSD: Samsung 980 Pro 2TB (Inserted into the M.2_1 slot)

I'm trying to install through UEFI rather than Legacy mode since from what I've read it seems better in all regards and is also a must (?) for the future if you want to install Windows 11 since you need to be able to enable Secure Boot (which you can only do through UEFI?).

• With CSM disabled every part seems to be detected by the motherboard, even the SSD but it does not show up in the boot menu (gives message: "The system cannot find any bootable devices.") and I can't set boot priorities.
• If I enable CSM the SSD shows up in the boot menu and I can set boot priorities, my USB with Windows 10 installation media on it does aswell with "UEFI:" before its information which makes me wonder why at least the USB wouldn't show up with CSM disabled if seems to be optimized for UEFI operations.
• If I keep CSM enabled but change all the sliders below to "UEFI only" then everything is as it was with CSM disabled.
• Loading Optimized Default settings does not help.

I've seen that there are tools that you can use to change a Windows 10 installation to UEFI mode if you didn't install through UEFI in the first place, but I can't find any information on how to install through UEFI in the first place if you're in a situation like mine.

As I wrote before, I'm out of my depth in this area so I would really appreciate some help!

 

[MeanMachine41]

How to install Windows in UEFI mode

1. Download Rufus application from: Rufus.
2. Connect USB drive to any computer. ...
3. Run Rufus application and configure it as described in the screenshot: Warning! ...
4. Choose the Windows installation media image:
5. Press Start button to proceed.
6. Wait until completion.
7. Disconnect the USB drive.

Best is to do a clean instal.

1. Download Windows.ISO. via Windows 10 using the media creation tool.
2. Create UEFI-bootable USB stick. via Rufus. ...
3. Change boot order to USB -> SSD. ...
4. Boot from USB. ...
5. Delete all partitions. ...
6. Complete Win 10 install.
7. Run Windows update.
8. Change boot order back to SSD only.

Don't forget to backup important files!!