To support a large disk array you just need a few things. - Lots of drive connectors. - That can be an 8 port SATA motherboard. - A SATA HBA card. I've

To support a large disk array you just need a few things. - Lots of drive connectors. - That can be an 8 port SATA motherboard. - A SATA HBA card. I've seen some with up to 24 ports, or some of these support port expanders which you would generally plug one cable into a hot-swap box of 2 to 4 drives. - A SAS HBA card. More expensive but you can use SAS drives with enterprise features. If you're okay with used drives you can sometimes find deals on 10 drives at a time at 25% of the new drive cost. - Lots of power connectors and a good PSU. If you have 8 SATA drives you need 8 SATA drive power connectors. Or you use hot-swap boxes and plug each one into one power connector, but watch the totals and remember drive spin-up can use 4-5 times as much power than normal. Numbers I've seen are 8W per active drive and 35W (maximum) for drive startup. But at any rate for large disk arrays the CPU can be ignored because almost anything will work. Hard disks are slow enough that you need like, 20 of them before the CPU speed starts to matter. With SSDs you can max out the controllers and PCIe lanes and even RAM bandwidth all too easily.