Hello everyone, I need your advice on how to properly setup a dual boot with Fedora 36 and Windows 10 in the same drive.
My previous setup was having Pop_OS on a SSD (500GB) and Windows on another SSD (4TB). Now I decided to switch to Fedora and I want to have both systems in the same drive (4TB). I formatted the disk and installed Fedora on it, leaving 2 TB unallocated to install Windows in it.
When I boot with the USB drive that has the W10 image, I get a message saying that I can’t install it on the unallocated because it is GPT partition. My understanding is that it should be possible but I don’t know how to proceed.
I would prefer to install W10 without having to format again since setting up Fedora to my liking has taken me some time already. I read in another post that the process should be to install W10 first and then shrink the drive and install Fedora. This is what I want to avoid.
Thanks in advance.
Windows 10 installs cleanly on a gpt disk when booting with uefi (in fact it requires GPT when installed to boot uefi). To me that sound like your bios is set to csm mode and that it booted legacy from the windows media.
There is a caveat though.
Windows must be installed first since it is very picky about the disk partitioning. After installing windows and shrinking the OS space using the windows disk manager it is very easy to install fedora in the now unallocated space. Both OSes share the same efi partition when installed on the same drive unless you have done some major config to allow 2 efi partitons.
An even easier method would be to create a VM within fedora (I use QEMU/KVM and virtmanager to do that) then install windows into the VM. Now you have total separation of the 2 OSes, with the added benefit that you can have both booted and operating at the same time.
Thanks for the quick reply. So I will have to start over, installing W10 first.
To me that sound like your bios is set to csm mode and that it booted legacy from the windows media.
Should I check this in the BIOS before formatting again?
Both OSes share the same efi partition when installed on the same drive unless you have done some major config to allow 2 efi partitons.
And I can’t do it the other way around because Windows is very picky right?
An even easier method would be to create a VM within fedora (I use QEMU/KVM and virtmanager to do that) then install windows into the VM.
The main reason for the dual boot is to play AAA games on W10. So the VM is not an option.
It seems everyone does that first. Though there may be ways around it, the windows boot loader will take control from grub and you would have to recover grub even if windows will install second.
I have never seen a report of successfully installing windows second when using a single disk.
yes, and if possible set it to uefi only.
It seems that way. Sharing an efi partition with windows is seamless and fedora is designed to do that.
Just so you know, shrinking the ntfs file system/partition within windows is really simple and has worked flawlessly for me for years. Make certain that you leave the freed up space as unallocated and there should be no problems.
Thanks for the help. I followed your advice and disabled CSM in the motherboard, formatted the disk and installed W10. Then I proceed with the automatic install of F36 in the unallocated disk space.
This is the result:
I was a little concern because in the Windows disk manager the unallocated space was sandwiched by two W10 partitions. But it seems Fedora was smart enough and it worked
Glad I could help and that you are now happy with the result.
Windows always seems to install onto 4 partitions like that and the last one is at the end of the drive. Fedora does not care where the space is, only that there is enough to do the install. Windows however does care about the partition numbering and if you do something that changes the partition numbering from sda4 to something else you may need to do a windows recovery from install media in order for windows to use that last (recovery) partition. Note that the partitions are out of order on the disk, and that is perfectly fine.