I've had Windows installed on an NVME M. 2 128 gb ssd for almost two years now, I remember installing modified Windows 10 on it (the ReviOS 2004 S1.0). I installed Windows on M. 2 with other disks connected to the PC, my 160 gb HD on SATA 1 and another 750 gb on SATA 2... Over time, the 160 gb HD started to cause a problem because it already had the most worn out useful life, so today I went after another HD to replace it. I hadn't changed anything in the BIOS, like changing the boot disk, I just changed it and turned it on, I didn't think anything would go wrong because Windows was installed on M. 2 and I had already selected it as the boot system at the time I I installed Windows. After I tried to boot the system, a notification started to harass me "reboot and select proper boot device or insert boot media in selected boot device and press a key", regardless of whether I reset or modify the settings in my BIOS (motherboard MSI B350 Tomahawk) the problem continued, until I decided to reinstall the 160 HD... And it worked! Windows loaded directly without even me having entered to configure something in the BIOS, but the reason I want to change it is because it is stopping giving a signal, it only worked when I left it suspended by the power supply cable (don't even try to tell me that this sucks, I KNOW! But he only showed signs of life when he got like that!). After logging into Windows and going into disk management, I noticed that my 160 HD is Healthy (System, Active, Primary Partition), and my M. 2 that Windows is installed on is Healthy (Startup, paging, Crash Dump, Primary Partition). Is there any way I can change the "System" disk so that my PC is not dependent on this broken HD occupying one of my SATA roads? (I used Google translate, sorry if anything mentioned is incongruous)