Nothing much, I've just activated Intel Rapid Storage Technology and after that i doesn't show my Sata HDD, but it still shows it's info in IRST, including the size of the disk.
It's the same info showed in IRST when I run Intel Optane
If I'm being honest I was just messing around, I don't really need to use the tool, just want my data back.
In order to get better information about your system, please download the Intel System Support Utility (SSU). Run the SSU scan (check "Everything") and save the results. The .txt file with the results please attach to your post.
You didn't 'activate RST'; what you did was enable the use of your HDD as a backup for your SSD. In technical terms, you created a RAID1 array combining your primary drive and this HDD. Why you did this, not knowing what it meant, I don't know. The contents of your HDD are probably hopelessly scrambled at this point, overwritten with a back up of your primary drive. I don't see you getting anything back. I hope you have an offline backup; you are going to need it.
Sorry, but reality bites,