Well, I've made some progress regarding the basic decisions i.e. type of board and chip etc.
Looking at even the lowest power CPUs available, when combined with the power usage of the motherboards and fancy graphics chipsets on the mATX and ATX boards, they seem to require about 3 times the power of an Atom on a mini-ITX board. As I'd like to be able to run the NAS 24/7 I've decided to try to find a suitable Atom and mini-ITX board and do a separate system for a HTPC later.
First off, a NAS doesn't require HD video output, so the latest ION chipset boards are out. I was checking out Intel's offerings and found that the 945GSE chipset produces about 6W TDP while the 945GC produces 22W (these are maximums). The 945GSE doesn't do quite so much in the graphics department and the 945GC but the main functions are similar. Memory bandwidth is about half... but not really critical here. The 945GSE chipset is paired with the Atom N270 for use in netbooks where thermal output is critical.
My other requirements have also been decided; these are:
- Gigabit LAN
- PCI Express slot - 1 lane is OK (2.5Gb/s so doesn't actually max out even one SATA connection - still it is more than adequate for storing data and even for playing back my DV files at 200MB/min)
- PCIe SATA controller card with 2 ports Silicon Image SiI3132 chipset. This will be connected via a flex PCIe riser. With two internal ports it can then have a SATA to eSATA connection to the rear of case.
- SATA port multiplier - 2 off to split each eSATA port. These would be in the drive enclosure, which will be hidden (sound insulated and fire insulated if I can manage - need some sort of fire damper for the vents)
- OS drive to be either Compact Flash or SSD for silence.
I found a SATA controller by Syba on
Newegg, but they don't ship outside the US... May be able to source from Amazon. Very cheap. Not sure of quality.
A mini-ITX board that seemed to be suitable is from
ibase called the MI810F. The "F" model has gigabit LAN. It has PCIe x1 port, and says it has a CF socket. I'm not sure where to actually buy it though.
Addonics have some port multipliers with a Silicon Image chipset.
The SATA controller chipset says that it supports RAID 0, 1, 10 etc but it doesn't actually do it itself, so software RAID will be required.
Can someone tell me how safe my data is if my OS drive fails? Does it keep some sort of catalog of the RAID that would be difficult to rebuild in the case of failure? Particularly if I didn't know exactly where each drive fit into the array.
Still to be determined:
- Case
- Drive enclosure
- Finding someone that has all the parts and that will ship to Australia.
- CF or SSD drive for the OS.
- OS to use. Generally use SuSE Linux. Think they may be one of the distros that support the Silicon Image chipsets. Haven't looked at FreeNAS as yet. May test it virtually first.
- Power supply for drive case and motherboard.