Question ASUS Z97 PRO GAMER board, M.2 (NVMe), SATA, UEFI and dual-booting


May 19, 2011
I currently have the following internal storage devices in my PC:

128GB Samsung 850 PRO SATA SSD (Linux installed, grub handles boot management)
256GB Samsung 840 PRO SATA SSD (Win10 installed)
2x optical SATA drives

The 256GB SSD is becoming a bit problematic in terms of capacity. I would like to replace it with an M.2 NVMe drive but I've never dual-booted with a mix of AHCI/NVMe, and will the UEFI BIOS just treat the NVMe drive as just another drive to boot from along with AHCI choices?

Tech Junky

Platinum Member
Jan 27, 2022
I would just make it simpler.

I use an SN850 1TB in my server for Linux and it's only using ~110GB of space. I would start off with a clean drive.

Do a fresh install of W10 on it w/ UEFI only enabled on the BIOS. This ensures that UEFI / GPT are invoked and configured on the drive vs cloning / converting the disk and then adding things.... though it's possible to retain all drive info / installed programs /'s just more time consuming. Then install Linux and you'll have a dual boot.

The other option is cloning or copying and getting your hands a bit dirtier with things. So, the UEFI boot needs to be 50MB in size to work. I know this from screwing around with converting my server drive from MBR to GPT to upgrade to ADL. There's some CSM issue with the board or UEFI that refused to boot an MBR drive for whatever reason. After figuring it out as the issue converting the drive took a couple of minutes and then it was back to normal.

On my laptop I wanted to move a couple of drives over to it and then slide W11 from the Gen3 to Gen4 as the primary. This got messy and eventually I tossed the idea and did a fresh install and copied the user / program files back tot he new install to avoid custom mapping everything again. The issue I ran into with cloning the drives here was the cloning didn't create a unique GPT ID for the partitions it just copied them across and the system though the Gen3 was the UEFI boot partition instead of the newer Gen4. Removing the Gen3 / boot repair on gen4 was just messy and time consuming.

I would recommend grabbing an enclosure for the NVME's and pull both from the system when placing the new one into the system to avoid conflicts as seen above. This also keeps your data safer if you don't have it backed up somewhere else. Depending on the board you might want to check for any bios updates and knock that out while you're playing around with things. Another option besides doing a complete disk clone is to do just the partitions and then run Grub with Linux and see if it picks up both OS's and adds them to the boot options.