Quote from: DeathAndTaxes on January 29, 2012, 05:47:37 PM

Quote from: xaxik on January 29, 2012, 02:25:42 PM

So my guess is, that they use EP3SL200 or 260.
It is definitely possible to put 3 fully unrolled pipelines into the 260
(at 150MH/s each) and, with some tuning, gain the advertised speed.

One question. Do you think it is possible for anyone with the experience necessary to design a custom FGPA board to get the power draw so wrong like BFL claims they did.

Yes, in fact that's an easy mistake to make.

Case in point: The CEO (and probably sole proprietor) of ZTEX did.

Before the 1.15x module, with its 8 Amp core voltage supply, came the 1.15d module, and the originally recommended supply for it
http://www.ztex.de/usb-fpga-1/pwr-1.0.e.html only sported a 3 Amp core voltage supply!

He found out the hard way that all these unrolled loops of SHA-2 cause something like 50% of all flip-flops on the FPGA to switch simultaneously, and
thus blowing even the most conservative power estimations out of the water.

Now he has discontinued the power supply module 1.0 and is instead offering the power supply module 1.1
http://www.ztex.de/usb-fpga-1/pwr-1.1.e.html with an 8 Amp core voltage supply, i.e. the same number of Amps that module 1.15x has.

Q.E.D.