Tilt UPDATE: So I tried installing windows again and still no luck. I redid my solus installation selecting GPT in rufus and still nothing. I searched through my bios again and I can say for sure that there is nothing that says anything about SATA or AHCI. There is also nothing that says anything about UEFI. So, I don't know what all that means for my bios. I kinda get the feeling that my bios is hiding some things from me.
Yes, it does sound like something is goofy here, blocking the installations for both Windows 10 and Solus.
If it was just Solus installation that was being blocked, that would be one thing, but I have never once seen a Windows clean install blocked when using a USB created using the Windows Media Creation Tool (MediaCreationTool21H2.exe), and I have used that tool many, many times over the years on my computers, on the railroad museum's computers, and on friends' computers. No matter how screwed up the computers were, I've never seen the Windows Media Creation Tool fail.
I'm going to do some internet research and see if I can come up with anything. You might want to enlist the help of Asus support. Unless your drive is defective somehow, it has to be something in the BIOS.
To help me with my research, could you go into your BIOS and report back the exact specifications of your drive(s)? As an example, the BIOS on this computer lists three drives (Windows 11 is installed on the Micron 256GB NVMe drive, Solus on the SK Hynix 128GB NVMe and the SATA drive is used for data storage):
SATA-0
Type = PNY 960 GB SSD
Device ID = PNYCS900 960 GB SSD
M.2 PCIe SSD-2
Type: 128 GB SSD
Device ID = SK HYNIX 2230 NVMe 128GB
M.2 PCIe SSD-1
Type: 256 GB SSD
Device ID = Micron 2300 NVMe 256GB
I'm asking for the information because that will give me a chance to research drive compatibility issues.
If both drives in your computer are M.2 NVMe PCIe drives, the AHCI/RAID setting should not make a difference, because AHCI/RAID is (as I understand it) applicable to SATA drives but not PCIe drives. I've never had an issue with AHCI/RAID on my computers because I install on NVMe PCIe drives, and use the SATA drives for storage.
WetGeek ran into a very nasty situation yesterday in which the BIOS on his new Acer Aspire laptop had enabled an Intel technology called VMD that threw a monkey wrench into the update process, and the Acer BIOS had the setting hidden. You might want to read that thread as background.
It sounds like this is a BIOS issue, and it is not obvious. At some point, in might make sense to reset BIOS to default settings and see if that makes a difference, but unless you've been mucking around in your BIOS, it probably doesn't make sense to do it at this point.
In any event, this is a puzzler.