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Cases for Multiple Single Board Computers?
dewboy asks: "We're trying to set up a rack of SBC's (Single Board Computers) that will allow us to plug a certain number of SBC's into a backplane which will provide power. All interfaces (mouse, keyboard, VGA, Enet, etc) are on the faceplates of the cards, so all they really need is power. All we've been able to find so far are chasses that support a single SBC and a (4-20 slot) backplane. What we'd like is a chassis that supports 20 SBC's. Has anyone found anything like this?"
California PC Products makes great cases, and has an 8U high case, and a 20 slot 4 segment backplane for it (allows 4 PICMG SBCs), with 13 drive bays. Check out the "13 bay rack server" and the list of passive backplanes at http://www.calpc.com/.
The best I've seen was a chassis that supported 4 systems in a 6U. They also did 4U cases with a 20 ISA backplane. I don't know what it'd take to get a backplane that only had the power pins connected to the slots, and not the bus signals.
I see one other problem, and that is all of the SBC's I've seen have parts that stick out (memory, or the processor in the case of Slot1's), and cause them to take up at least 2 slots. One system, I lost 4 slots to the SBC. It had a slot1 processor on one side, a big heatsink on the BX chipset on the other side, and the cards I needed to put next to it were full length with daughercards.
I'd check with http://www.amer.com/ and http://www.lannerinc.com/ and see if they can point you to something that'd help. Amer.com used to have a picture in their catalog of their 6U multisystem chassis with SBC's in every slot, but I don't think it'd work that way.
Worst case, get the 20 slot backplane, and cut some traces yourself.
Lastly, watch the cooling issues, and make sure your power supply is sized well.
Hopefully this helps some.
Anyone still have the link for the medusa case mentioned a few months ago on Ars or HardOCP?
This of course is what youre looking for. Of course a rack wil do nicely too.
If you are looking for a backplane to supply power only, why not either make your own backplane and solder on connectors, or modify an existing backplane and cut the signal lines, leaving all power and ground lines attached?
:) ... it is fast but not cheap. Wirewrap also has a limited life (10 or so years I think) in 'normal' environments. That is why it is best for prototype environments.
If you are making your own plug compatable SBC, just use the power only and ignore the rest of the lines.
Another option, is get wirewrap set of sockets, and roll your own buss
... "When you pry the source from my cold dead hands."
www.emacinc.com
Under their catagory of SBC PC Addons, they have an item listed as "20 slot Multi-system Rackmount Industrial PC Chassis."
There is no picture, but they can (hopefully) send you the info.
Since I gave up hope, I feel much better.
Why not just buy a rack ? They are rather affective for housing multiple machines.
EOT
Such devices are also popular for computer telephony, so you can also search for sites which refer to that. But first start with Computer Telephony magazine. They have buyer's guides and related info.
If you haven't bought the SBCs yet, also consider VME devices...
The next spin of Intel chips will take up to 100W of power. Combine that with 25W/PCI card, fan, hard drive, CD-ROM, etc. and you can easily blow a 400W power supply in no time flat.
And more fun: cooling! At 100W/CPU, you'll need a lot of airflow to keep it below 55C, which is where things like the hard drives start to burn out. And probably the power supply too.
20CPUs in a single chassis isn't going to happen. 4 is a better possibility, since you can load-share 2 400W power supplies in a 19" rack.
Given space requirements, you can do two 400W supplies, but probably not many more than that.
-- Ever notice that fast-burning fuse looks exactly the same as slow-burning fuse? I didn't... (Edgar Montrose)