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Right. This is confusingly explained, but it gives sense to all the numbers.
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We have a good guess. They claim their 3.5 GH/s chip is USB powered. So there you go. 1400 MH/watt (or better), which means if the 1 TH/s Rig is using the same chips in parallel, 714 watts. This 130nm shared wafer research ASIC can achieve 140 MH/J performing SHA-256 on a streaming input.  http://rijndael.ece.vt.edu/sha3/index.htmlKeep in mind: a) this was designed as a testbed for SHA-3 and runs at only 50 Mhz. Not exactly ideal for SHA-256. b) it is on a 130nm platform. 65nm would be roughly 4x the MH/J. 45nm would be roughly 8x the MH/J c) VT own data shows the chip can easily run at much higher clock speed without increasing the gate count. d) the design is optimized for multi-round hashing which is ill suited for Bitcoin (where single nonce header is hashed once, check and discarded or returned). e) it was designed as research project at my alma mater Virgina Tech (hardly ultra cutting edge fabrication). Despite all those handicaps this unoptimized (for Bitcoin hashing) ancient 130nm multi-purpose shared wafer chip built at a university research fab can achieve 140MH/J. With optimization and a modern 45nm process >2 GH/J is certainly "possible". Once again before you misinterpert. I am not buying a BFL product (or any mining hardware). I don't really care if BFL has the greatest hasher on the planet or the best scam. I agree it is foolish to give money upfront and hope for the best. All that being said you undermine your argument when you claim the possible is impossible. Is a 3.5 GH/s ASIC running on 3.5W possible? Most certainly.
Will BFL produce it (and on time, and on spec)? Who the frack knows.Are you sure that's right? They listed 13.76mJ/Gbits. Hmm, isn't it wrong? I think the paper contradicts itself because Table III lists SHA-256 doing 1.51Gbps at 5.18mW measured (first Power column, not the second). That would be 5.18/1.51 = 3.43 mJ/Gbits. Why would the table also lists 13.76 mJ/Gbits? I emailed the authors for a clarification. |
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Announcement to all: if I mine the first 25BTC block, I will keep it to myself  |
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Bitcoin is diametrically opposed to all existing electronic currencies. It is "unseizable digital gold". There is a fixed supply of coins. Transfers are irreversible. It runs over a peer-to-peer network, not under the control of any company.
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That's interesting; so they are using USB hubs instead of the "X-link" board that we saw that has SATA connectors. I wonder if the SATA is for a different application or if USB was deemed more reliable or what.
Of course not. I am sure that BFL were initially planning to use the X-link board and Raspberry Pi to make a much more polished mini rig, and then decided to do without them in order to cut corners and not be (more) late on their schedule. |
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I have been in contact with Pico Computing, about a year ago, to investigate mining on their FPGAs. But it turned out that their LX150 boards ($1200+ per LX150) are insanely expensive compared to, say, Ztex (starting around $220 per LX150).
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miaviator: you just bought a bunch, you want more?
Trance104: I will do $400 cash only. Via paypal, I would ask $415 to cover the increased fraud risk, and I would only sell 1 card at a time.
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Where did you get 16:40 from? just random or is it in some spec.?
It equals to a nice round number: 1000 sec. Only programmers notice these things |
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Only 10 cards left! It takes a while to sell 40+ cards... :-)
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My 7-port USB switches use a single controller chip (Rosewill RHB-330, based on the Terminus-Tech FE 2.1 controller). I carefully selected them over switches using ganged controllers for better reliability.
catfish: I have 13 quad 1.15y boards on the same PC (52 FPGAs total), and the setup is very reliable. FPGAs are detected all the time. I have not measured current flow through my USB cables, but it is probably small. Note that I do power my boards via the pluggable terminal, not via the 5.5mm jack. The mechanical and electrical design of the pluggable terminal is superior to the jack which reduces resistance and probably helps reduce current flow in the USB cables. (Stefan recommends to connect 2 ground wires to the pluggable terminal, but I didn't even bother, as I have no reliability issue with 1 ground wire.)
Also, my FPGAs are powered by the same PSU that powers the host PC. I imagine that using 2 different power supplies for the PC and the FPGAs might increase the risk of current flow in the USB cables.
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Show us a picture of the burnt PCB, and we may be able to tell you what caused the fire base on the source of ignition.
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ASIC are like Buying a Car that can only turn Right.(SHA-256 ASIC)
What happens if someone finds a pot hole in the road? (SHA-256 Weakness)
Turn left by turning right 3 times successively? Metaphor fails |
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There are enough. More than enough, even with rich companies hogging entire address ranges with their class A networks. It's called NAT.
http://blog.zorinaq.com/?e=48 |
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My theory: vitaliy_www sells bitcoins to his clients paying in USD or RUB; in other words it is a dark pool to not impact regular markets (MtGox, etc). And he needs hashing power to get these bitcoins. This is supposedly the same business that pirateat40 claims to be doing via gpumax & btcs&t. My advice to people: don't mine for vitality or pirateat40, let them buy the coins on the open markets to let the exchange rate rise |
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The investment round is closed. I will disclose a bit more info as to what happened later today or tomorrow.
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I see the following possibilities:
1. this is some kind of parody
2. mrb's forum account got hacked
3. it is time for me to retire coz it seems everyone in Bitcoin get's 50 times better interest (when non compounded) than old conservative me.
It's not #2, I signed the msg with my OTC PGP key |
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