[twentysix]

Just nitpicking, but isnt the unit supposed to be GHz?

400 Giga Cycles/s makes more sense, unless I am missing something.

[mrb]

Gh/s means gigahash/second. 1 billion "Bitcoin hash" per second. With 1 hash defined as SHA256(SHA256(80-byte block header))

I don't have my notes with me but these Bitfury chips run around 150-250 MHz individually. There are 256 of these chips in the 400 Ghash/sec device. Each spits out about 10 hashes per clock cycle.