HDD device not found.

@maitakemaitake yes, that "the HDD started making noises" sounds like a mechanical failure of your HDD. Unless you have had a second HDD or another drive connected to your computer, it is highly unlikely that your "system has backed up my files". It will do so only if either programmed to do a backup or if you prompted it to backup. If it did so, you would know where you told it to back up too.

Since you consider those "precious files", this would be case where you would need to contact a data recovery specialist since it will involve to work on the inside of your HDD (platter, actuator arm, read/write heads etc.). Tying to do this yourself might diminish your chances of recovering those files.