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Re: BFL Single and BFL mini-rig seems to have inferior performance
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bitfury
on 03/07/2012, 02:15:13 UTC
Quote from: tidus_13 on July 03, 2012, 02:06:32 AM
Quote from: bitfury on July 01, 2012, 02:48:56 PM
Quote from: BlackPrapor on July 01, 2012, 02:11:46 PM
Maybe he realized that there is no way to compete with BFL and wants to get a job there, by showing how 'smart' he is. Otherwise, he'd just make something better himself Smiley

Well. I don't need job with them, but I may sell to them solution of course. Right now they have more than enough money just to buy some know-hows about sha256. And looking at their hash-rates I clearly see that they need it :-)

As for Spartan solution - it is already fastest, and if yohan's prices for board combined with my bitstream price per Mh/s would be $0.53 / Mh/s for FPGA (1200 Mh/s for $640). This already beats BFL prices. If my licensing per-spartan would be applicable ($25 per chip) - then it would be 1200 Mh/s for $740 - $0.616 - again beats BFL. But - yohan prefers 840 Mh/s :-) While our capabilities do not allow to deploy quickly and cheap solutions.

For ASIC solution it is tougher - because this sets stakes higher. And I don't like to happen competing with phantom like it was with 20 W / 1050 Gh/s single... Trying like crazy getting 500 Mh/s from single Spartan :-) And then seeing that no magic was there, just some marketing fraud. I think they did it with this intention as well, to make others spending time trying to compete with the thing you can't :-) And then simply say "oops" - it is 80 W but not 20 W :-) Sorry - this is the thing that I won't forget :-) Quite happy that mini-rig was done differently. :-)


so your bitstream it´s  300Mh/s? per Spartan Chip?  it would be 600Mh/s at Icarus?

Depends. Potentially yes. 12 W power per Spartan Chip. That power makes it difficult to use on many boards, for example with ZTEX boards.

You may look on our web site how many there capacitors below the chip (www.bitfury.org). On Icarus it maybe just 260-280 Mh/s, because it maybe wise to _lower_ voltage there to 1.15 V and decrease frequency accordingly. So it would run about 210 Mhz - 220 Mhz and consume about 9 - 9.5 W taking about 8 Amps power.

But exact combination of voltage and frequency should be determined based on power supply components and bypass capacitor calculations.