I've just bought a new PC. It's a refurbished HP EliteDesk 800 G1 Tower which originally had (I assume) Win 8 installed but came with Win10 on a 1 tb HD.
After certifying the Win10 s/w supplied I've replaced the HD with the 2 TB one from my old PC which has a fully updated Win10 operating system(originally the free download from Microsoft) as well as all my programs/data etc installed. It works perfectly and has 3 partitions - one for program installation (ie C) and another 2 called User (D) which has my data and Linux (E) which I originally set up in an abortive attempt to install a Linux OS.
A few months ago I bought a 250gb SSD as an experiment and successfully installed it in my old PC. I use it as a data back-up. I also installed all my RealFlight 9.5 s/w on it as I thought it would be faster.
I've put the SSD drive in my new PC but I'm having huge difficulties in getting the PC to 'see' it. The BIOS defaults to setting up the SATA interface as AHCI with IDE and RAID as alternatives. If I change to IDE, the system won't boot properly so resetting to the default AHCI is needed. Then the PC boots OK and, moreover, now my SSD drive works perfectly! However, if I switch off, the next time I boot up, the SSD drive has disappeared!
Obviously, it's not a show stopper but never the less very annoying and puzzling. It's obviously something to do with SATA set up but what? I'm very out of date technically (I've been retired since 1995) and in any case I didn't delve much into IBM PCs other than using them (Win3.1). All my s/w was written in Motorola 68xx assembler or a bit of 'C' to drive h/w I'd designed so I'm not a total dummy but I'd appreciate a little help from someone a bit more current.