You don't need a 1U control unit.
Each Sierra is self contained (cooling, power, 3x ASIC modules, case, and a controller/host). The only advantage of the 1U control unit is that it would allow a single host to control up to 10 Sierras (30 hashing modules). Also HF has indicated that the modules are connected to the "host" by USB. This means anything which can run cgminer can be a host. You can use the included rPi host in the Sierra and/or BabyJet or you could connect multiple hashing modules to a dedicated computer for a custom solution. Although HF hasn't provided the specs my guess is the 1U "control unit" is just an entry level 1U server running some form of linux and cgminer. Instead of configuring a farm through the 10 Sierra rPi hosts all 30 modules are connected by USB to the single server for ease of management.
Still if you want to go w/ a BabyJet instead, HF has indicated they intend to sell just modules in the future although no date or price has been provided. A single sierra is likely a better deal though. as to upgrade a Babyjet to handle a second module will require a larger power supply and a second cooling loop (or larger radiator). The sierra comes out of the box ready from day 1 for 1.2 TH/s.
Each Sierra is self contained (cooling, power, 3x ASIC modules, case, and a controller/host). The only advantage of the 1U control unit is that it would allow a single host to control up to 10 Sierras (30 hashing modules). Also HF has indicated that the modules are connected to the "host" by USB. This means anything which can run cgminer can be a host. You can use the included rPi host in the Sierra and/or BabyJet or you could connect multiple hashing modules to a dedicated computer for a custom solution. Although HF hasn't provided the specs my guess is the 1U "control unit" is just an entry level 1U server running some form of linux and cgminer. Instead of configuring a farm through the 10 Sierra rPi hosts all 30 modules are connected by USB to the single server for ease of management.
Still if you want to go w/ a BabyJet instead, HF has indicated they intend to sell just modules in the future although no date or price has been provided. A single sierra is likely a better deal though. as to upgrade a Babyjet to handle a second module will require a larger power supply and a second cooling loop (or larger radiator). The sierra comes out of the box ready from day 1 for 1.2 TH/s.
I thought so too but it turns out that the BabyJet is self contained, it has the Rapberry Pi, but the Sierra does not:
Quote
We don't want to risk overloading the limited resources of a Raspberry Pi by running more than two mini-boards (formerly 'modules') off one of them.
So we recommend something more powerful for one or more Sierras.
So we recommend something more powerful for one or more Sierras.
so you will have to provide some kind of system running cgminer with USB to hook up the Sierra to.
The Sierra is not self contained
