A repurposed HP Pavillion TP01-0066 Desktop w/Ryzen 3700X, 256GB NVME SSD and 32GB RAM, with 5x USB 3.0 HDD's attached for mass storage and onsite backup using dirvish[1] and rdfind[2]. It has a fan but is usually silent.
[1] https://dirvish.org/ [2] https://github.com/pauldreik/rdfind
I use rdfind to deal with this: https://github.com/pauldreik/rdfind
I use and test assorted duplicate finders regularly.
fdupes is the classic (going way way back) but it's really very slow, not worth using anymore.
The four I know are worth trying these days (depending on data set, hardware, file arrangement and other factors, any one of these might be fastest for a specific use case) are:
https://github.com/jbruchon/jdupes
https://github.com/pauldreik/rdfind
https://github.com/jvirkki/dupd
https://github.com/sahib/rmlint
Had not encountered fclones before, will give it a try.