For 10 Gbps equipment look at Mikrotik switches, a 4 port SFP+ one was around $130 when I bought it and the PCIe NICs were $50 a piece. I used DAC and AOC inste

For 10 Gbps equipment look at Mikrotik switches, a 4 port SFP+ one was around $130 when I bought it and the PCIe NICs were $50 a piece. I used DAC and AOC instead of UTP cables, they were $20-$50 each depending on the length, I paid for the whole thing a bit over $600 (6 SFP+ ports in total on 2 switches). I use TrueNAS and the cache works only for reads, it helps with navigation of the folder structure (tens of thousands of photos, for example), but not with writes and not with most reads. Some other solutions can do write caching on SSD, that may improve the performance over 10 Gbps network a lot, but for 1 Gbps cache is not that useful.