On Dec 24, 2007, at 1:39 AM, Richard wrote:
Origin2000 and Onyx2 Deskside and Rackmount
Installation Instructions
Document Number 108-0155-002
12/96
pg. 6-36
"Caution: You cannot install CrayLink interconnect cabling on a
standalone deskside system because of power grounding
requirements. The power differential between two interconnected
modules should not exceed 500 millivolts; otherwise severe damage
can result to boards and other components inside the chassis. The
power distribution unit (PDU) inside the rack provides a common
ground source for the modules. In addition, the groundstraps are
installed on multirack configurations to help provide common
grounding across the racks as described in Section 6.16"
That seems about as blunt as you can get.
I'm not sure about that- you can CrayLink to Origin 200s together, the
only requirement being the common ground (plug them into sockets with
the same ground, run a thick ground between the chassis, or (as I have)
stack them one on another if they don't have the skins).
If you can do it with an Origin 200, then you can do it with a Origin
2000, since the hardware is very similar. You might need to get
creative with the grounding, though, and make sure it's done well
(perhaps two grounding straps of ~12AWG connected to different
locations). Perhaps SGI did not design the ground point into the O2k
deskside as they did in the O200, but we're a creative bunch here.