I compiled a table comparing the voltage converters supplying VCCINT to the Spartan-6 LX150, across all board manufacturers. The table below lists the maximum current that can be provided to each FPGA, as well as the efficiency of the converter at 8A
(for 12V input, and 1.2V output):
(*) Some batches of ICARUS boards use the TPS40192 (rated 15A), others use the TPS40193 (rated 20A).
(**) The nice thing about the ModMiner is that you can decide to plug only 3 FPGAs in the mainboard, to give 13.3A to each FPGA, as they share a common 40A-rated voltage regulator.
eldentyrell: can you comment on how much current does your TML bitstream pull?