Paul Vixie wrote:
i'm spec'ing datacenter space at the moment, so this is topical. at 10kW/R you'd either cool ~333W/SF at ~30sf/R, or you'd dramatically increase sf/R by requiring a lot of aisleway around every set of racks (~200sf per 4R cage) to get it down to 200W/SF, or you'd compromise on W/R. i suspect that the folks offering 10kW/R are making it up elsewhere, like 50sf/R averaged over their facility. (this makes for a nice-sounding W/R number.) i know how to cool 200W/SF but i do not know how to cool 333W/SF unless everything in the rack is liquid cooled or unless the forced air is bottom->top and the cabinet is completely enclosed and the doors are never opened while the power is on.
If you have water for the racks: http://www.knuerr.com/web/en/index_e.html?products/miracel/cooltherm/coolthe... (there are other vendors too, of course) The CRAY bid for the DARPA contract also has some interesting cooling solutions as I recall, but that is a longer way out.