You're knocking on something I hit on back in June. Presume they're running 7.5 watts per mh, that's 1875 watts total. The photo they've been showing is of a ~19" case @ 4U (7"). This has 10 6xPCIE power ports, each rated at 75 watts. There's nowhere else in their design, or any photos, for any supplemental power. This limits that device to a nominal 750 watts, or, 100mh.
This would mean the photos are of a 50mh unit, AND/OR something in their design isn't right, AND/OR they plan on burning up power ports, AND/OR their chips are the most efficient in the world and run far less than projected. The PCB shown looks to be roughly 15x5", which means that there wouldn't be any room left in the case for more boards once you add heatsinks.
This would mean that physically, the case pictured, can only hold about 120 chips, which according to their projections is 180mh. To reach 250mh, they'd have to overclock by 39% which means an even higher wattage use.
For a 10 board @ 12 chip case to push 250mh, each chip would have to run at 2.1mh. For it to be within allowable CE spec for the 6xPCIE connector, they couldn't be pushing more than 3watts per 1mh. Anyone familiar with KNC's recent fiascos with the 6xPCIE's will know what happens when they're pushed too far.
To give an idea of current real-world at-the-wall ratings reported by folks:
Gridseed GC3355 55nm: 26.9w/mh
KNC Titan 28nm: 5w/mh
AlphaTech's gear would have to be almost twice as efficient as KNC's to meet their "fastest and most efficient" claims, AS WELL as actually shipping the advertised hashrate per box. Not saying it's impossible, but there's a lacking probability.
Yes, we talked about this a while back. Alpha are using 40nm technology so I'd be interested to see their real world power consumption figures. Don't even get me started on stuffing 14 boards into that case. I don't see how they're going to do it and still get heatsinks in. As I pointed out with photos in this post
https://bitcointalk.org/index.php?board=160.0 every other manufacturer has A LOT more space for heatsinks and cooling. They're going to need the worlds most efficient chips to stick 168 of them into that case without the whole thing going up like a Roman candle.
But we're assuming they're going to ship anything at all, which at this point is highly unlikely so the point is probably moot.