Do I Need to Convert My C Drive from MBR to GPT to Install an NVMe SSD?

I have Windows 10 and an Asus Z97-AR motherboard. My C (OS) drive is a SATA SSD. My present problem is that the PC does not recognize the NVMe in its M.2 port despite the motherboard boot system being UEFI BIOS. I have finally discovered that the C drive (OS) is MBR partition style, whereas it needs to be GPT for reasons of UEFI compatibility. Can I convert the MBR to GPT without having to wipe the C drive and the OS with it?

According to what you say, your NVMe SSD can't be recognized by the computer in its M.2 port. To help you fix the problem, I prepared three options that you can try to make your NVME SSD detectable. Before going through the details, reinstall the NVME SSD to ensure it's not a connection error.

1. Enable PCIE Support

Quick steps to enable PCIE support as below:

Check its status to see if it's enabled. If this method doesn't work, continue to try the next.

2. Switch the boot mode

Ensure your computer can support Legacy BIOS before operating. Then, you need to disable the UEFI mode to set up the Legacy mode in the boot settings. If the above two solutions can't solve the problem, you may need to convert the disk from MBR to GPT.

3. Convert MBR to GPT

You can convert the MBR to GPT without wiping the C drive and the OS on it by using EaseUS Partition Master. Its disk converter feature allows you to convert disk between MBR and GPT quickly and safely.

Follow the easy steps to convert your system disk from MBR to GPT using EaseUS Partition Master:

Notice: No data will lose when converting MBR to GPT via EaseUS Partition Master, but backing up the whole disk would be necessary to prevent an unexcepted data damage.