With the exception of Toaster RAID #1, the systems have all used an external "brick" power supply that is similar to what is used to power laptop PCs. Toaster RAIDs #2 and #3 had modest power requirements: 2.9 V for the CPU and 5/12 V leads for the drives, motherboard, and a small fan. Toaster RAIDs #2 and #3 are powered by a small 12 V supply that connects to a power distribution PCB inside the toaster that measures about 1.5" by 3.0" by 0.5".
Logic Supply, Mini-ITX.com, Polywell, and Mini-Box.com all have Web sites that offer a wealth of information about new compact internal distribution units and I quickly learned that Toaster RAID circa 2009 would need a more robust power supply. The power rating of the CPU alone was 45 W. There would be four instead of two drives, a high-RPM CPU fan, and a smaller fan to cool the Nvidia MCP78s chipset. A helpful technician at Polywell suggested I use a 12 V 110 W power supply with a new "pico PSU" internal power distribution unit. I also had a few 5 V/12 V Y-splitters and a couple of SATA 5 V/12 V HDD power adapters in hand.
This is the internal power distribution unit for the mini-ITX motherboard. It connects directly to the motherboard. A series of Y-connectors is attached to the 5 V/12 V lead to power the rest of the system.
The internal power distribution unit and the external 12 V/120 W power supply
Getting The System To Come Up
First I put Fedora and CentOS on the system. This was to make sure the system came up and the chipset, SATA, Ethernet, and other drivers were available, and that all the board components could be detected. This worked fine so I pulled down OpenFiler and FreeNAS.
OpenFiler failed to detect the hard drives. FreeNAS installed fine, but failed to detect the Realtek NICs. Some quick Web research indicated that this was a known issue and could be fixed in one of the 32-bit daily builds of FreeNAS, which I downloaded and installed without issue. Using FreeNAS, I set up the system, created a RAID 5 array, and moved a bunch of files from my Mac and notebook to the new server.