NAS using old hardware and HDD-s

[JeyTee84]

I have a bunch of "scrap" 2.5inch and 3.5inch drives laying around from super slow ones to properly working ones, 120GB to 1TB ones.
Is there a quick and dirty way of setting up a "smart" NAS PC using some old harware and a bunch of these drives?

Here's what im thinking: I have an old mobo with an Athlon II X4, and 4GB RAM in it. It has 6 sata ports. Could I install a NAS OS on it that could use the disks in a "smart" way? Like put in a 120GB SSD as a cache drive and plop in a few of these random HDDs that would be used in a redundant way?

Thanks in advance for any help, tips and ideas.

(reviving this old thread)

[Electronics Wizardy]

Unraid would probably be the best for this use case. Easy to use, easy to add drives, works great with mixed drive sizes, and has a parity drive for redundancy.