Understanding the Boot Priority Conflict
When installing Pop OS alongside Windows 10, the Linux installer typically installs the GRUB bootloader into the EFI System Partition (ESP). However, many modern motherboards, particularly those from ASUS, have a default behavior that prioritizes the "Windows Boot Manager" entry above other operating systems. This happens because the UEFI firmware scans for specific GUIDs associated with Microsoft’s bootloader and places them at the top of the list to ensure fast startup times for the primary OS.
This conflict is not a bug in Pop OS or Windows, but rather a feature of how UEFI handles multiple boot entries. If you do not intervene, every time you power on your machine, the system will bypass GRUB entirely and launch Windows directly. This makes it impossible to select Pop OS unless you manually interrupt the boot process or access the one-time boot menu repeatedly, which is inefficient and frustrating for daily use.
Accessing the ASUS BIOS/UEFI Settings
The first step in resolving this issue is entering the firmware interface where boot priorities are managed. Shut down your computer completely. Once the machine is off, press the power button and immediately begin tapping the F2 key repeatedly. On some ASUS models, you may need to press Delete instead. You should see the ASUS logo or a black screen with text indicating you are entering Setup mode.
If you are unable to enter BIOS using keyboard shortcuts, you can also trigger it from within Windows. Go to Settings > Update & Security > Recovery, and under Advanced startup, click Restart now. After the reboot, select Use a device and choose UEFI Firmware Settings. This will restart the PC directly into the BIOS interface. Ensure you are in the correct interface; look for tabs labeled Boot, Startup, or Advanced.
Manually Reordering Boot Entries
Once inside the BIOS, locate the Boot tab. Here you will see a list of devices and boot options. Look for an entry named Windows Boot Manager and another named ubuntu, Pop!_OS, or simply GRUB. The goal is to move the Linux entry to the very top of the priority list.
Use the arrow keys to highlight Windows Boot Manager. Press F5 or F6 (check the bottom of the screen for the specific key legend) to move it down the list. Then, highlight the ubuntu or GRUB entry and move it up until it is number one. Some newer ASUS boards use a mouse-friendly interface where you can simply drag and drop the entries. Ensure that the Linux bootloader is listed before any other Windows-related entries.
Fixing Windows Boot Order Issue in Dual Booting Pop OS and Windows provides additional context if your system lists multiple redundant entries that need cleaning.
Disabling Fast Startup in Windows
Even after changing the BIOS order, Windows can sometimes hijack the boot process again due to its "Fast Startup" feature. This hybrid shutdown state hibernates the kernel, which can lock the EFI variables or cause the firmware to reset priorities upon detecting the Windows partition. To prevent this, boot into Windows and open the Control Panel. Navigate to Hardware and Sound > Power Options.
Click Choose what the power buttons do and then click Change settings that are currently unavailable. Uncheck the box next to Turn on fast startup (recommended). Save changes and shut down the computer completely. This ensures that when you power on, the UEFI firmware performs a cold boot scan, respecting the order you set in the previous step without interference from a hibernated Windows state.
Verifying Secure Boot and Legacy Support
In some cases, mismatched security settings can cause the bootloader to be hidden or deprioritized. In the BIOS Security or Boot tab, check the status of Secure Boot. Pop OS supports Secure Boot, so it should remain enabled for maximum security. However, if you encounter issues, try toggling it off temporarily to see if the GRUB entry appears correctly in the boot list.
Additionally, ensure that CSM (Compatibility Support Module) is disabled if you installed Pop OS in UEFI mode. Mixing CSM and UEFI modes often leads to boot order confusion. If your system is set to UEFI only, make sure the Windows Boot Manager is still present in the list but placed below the Linux entry. If you have previously modified boot flags using tools like bcdedit in Windows, these changes might override BIOS settings. In such cases, resetting the NVRAM in BIOS may be necessary.
BIOS won't recognize bootloader: Troubleshooting Guide offers deeper diagnostics if your GRUB entry is missing entirely from the list.
Finalizing and Testing
After making these adjustments, press F10 to save and exit. The system will reboot. You should now see the GRUB menu appear, allowing you to choose between Pop OS and Windows. If Windows still boots automatically, re-enter the BIOS and verify that no other boot option, such as a network boot or USB drive, is interfering. Consistent ordering in the primary boot priority list is key to maintaining a stable dual-boot environment.
Frequently Asked Questions
Why does Windows Boot Manager keep reappearing at the top?
This occurs because Windows updates or certain motherboard firmware defaults prioritize the Microsoft GUID. Additionally, enabling Fast Startup in Windows can lock the boot configuration. Disabling Fast Startup and manually setting the priority in BIOS usually resolves this permanently.
Can I fix this without entering the BIOS?
No, boot order is controlled by the UEFI firmware, which cannot be changed from within the operating systems. You must access the BIOS/UEFI settings via F2/Del or the Windows Advanced Startup menu to rearrange the boot entries.
What if I don't see the Ubuntu or Pop OS entry in BIOS?
If the entry is missing, your system may be in Legacy/CSM mode while Pop OS was installed in UEFI mode, or vice versa. Check the boot mode in BIOS and ensure both OS installations use the same method. Refer to guides on recovering lost bootloaders if the partition is intact but not listed.
Does Secure Boot affect the boot order?
Secure Boot itself does not determine order, but it can hide unsigned bootloaders. Since Pop OS uses signed kernels, Secure Boot should work fine. However, if GRUB is not appearing, temporarily disabling Secure Boot can help diagnose if signature verification is causing the firmware to skip the entry.
Will resetting BIOS clear my custom boot order?
Loading default settings in BIOS will reset the boot order to factory defaults, likely putting Windows back on top. You will need to re-enter the BIOS and manually reorder the entries after any major BIOS update or CMOS reset.