Hi,
getting my first Little SC without PSU. Two more should follow soon, another 60GH/s SC as well,.
Having them all delivered w/o PSU due to customs problems in Germany.
What PSU should I buy to replace BFLs PSU with?
So you're wanting to run 3 Little Singles, and one SC Single?
Little Singles are about 150W each, and a SC Single is 275W? That means you need at least a 60A rail, along with something that can supply 8 PCIe connections. Narrowing that down to a Single Rail, something that's 80Plus Gold, and fully modular (to cut down on the cable mess), and you're looking at
THIS ONE. There are a few other options, but this one is by far the cheapest.
Because you won't necessarily be hooking it up to a host PC, you could always use a paper clip to turn the PSU on, or buy one of these from Cablez:
I also now provide switches for your ATX power supplies if it is not the host system: Can be for modular and non-modular types. Pricing is
Please PM each

BUY HERE.
I was just looking into it this afternoon, and this is what I would do.