I repurposed a micro Dell Optiplex 3060 with 8GB RAM and two external HDDs totalling 9TB of space. The CPU is an i3. The whole thing takes less space than a book.

I have lz4 enabled and the gigabit link is almost completely saturated when transferring: 119 MB/s out of the total theoretical 125.

No ZIL, no L2ARC devices are attached. That thing is _flying_ as a home NAS.