I've disconnected default SSD (Samsung) in order to connect new emty SSD (Transcend). I was in need to clone my laptop's HDD on this new SSD as a transit SATA port, because I've got only one SATA to USB connector, used by laptop's drive. I've successfully cloned my drives, disconnected all new drives, connected default SSD (samsung) and - no OS boot. I've not changed ANY BIOS settings.
Ok. I've a look on BIOS settings, and I see NEW (almost disconnected) SSD (Transcend) as bootable device. And NO Samsung SSD in boot device. Only Transcend which is no more connecned to motherboard. In SATA I see only Samsung SSD connecned, but I don't see it in BOOT section.
I've restored to factory and than to default settings with no effect. Than I've cleared CMOS - no effect. I see disconnected SSD device in BIOS BOOT section. What I'm doing wrong?
I've changed firmware of my BIOS. Downgraded it up ti 1.2.3 version, than upgraded it again. No effect. Old SSD doesn't appear. BUT in Legacy boot disconnected drive is still present. I cannot delete it. cannot change it to connected SSD drive. I guess it's somewhere in Legacy Option ROMS, and must be changed - but there are no options in this BIOS section. I'm gonna hate UEFI
Finally I didn'd find another solution, absent SSD is still in BIOS listing. And there is no way to boot in legacy mode with old-one. So I had do change boot parameters to UEFI, added security boot, and reintalled from Win 7 to Win 10...