The 80Mhash/s design draws less than 5 Watts. With a micro and Ethernet that might be a tiny bit more, but not much. The power regulator will also take it's share. So, I dunno, let's call it 10 Watts. They will basically always be profitable. It just might take a year to pay them off first.

The 80Mhash/s design requires cooling from a small fan. I use a small 5 Watt fan and it does the job. You could probably get smaller, or even just use a passive heatsink.

Down clocked to 50Mhash/s and it doesn't even need cooling at all. You could easily stack them, with one micro controller driving several FPGAs.

80 Mhash/s is the best I've gotten so far. My next goal is 160 Mhash/s inside a slightly larger FPGA. I'm by no means a guru here. Someone with more experience than I could easily redo the adder chains and possibly redo the register spacing to pull maybe 120 Mhash/s out of the chips I quoted above.

I have the exact same card from NewEgg and can only get 850Mhz out of it. My silicon bows to your superior batch

Using what I've developed to-date, these would be the costs (USD):

DIY Kit - 80MH/s, computer required

* Altera DE2-115 Development Board - $600

Total: $600



Fairly soon I hope to have the LaunchPad micros up and running. So that'd be:

Future DIY Kit - 80MH/s, runs independently (no computer)

* Altera DE2-115 Development Board - $600
* LaunchPad eval kit - $4
* Ethernet module - $25

Total: $629


Supposing a custom board was made:

Possible Custom FPGA Board - 80MH/s, runs independently (no computer)

* Altera Cyclone 4 C115 chip - $400
* Custom PCB & parts - $20 - $50?
* Micro - $4?
* Ethernet - $15?

Total: $469


Anything with a question mark is an educated guess. And of course a custom board has design costs associated with it, which would have to be folded into any quantity of units sold.

Huzzah! I got my LaunchPad microcontroller kits today. $4 USD each, shipped.  Too bad TI's development tools have terrible licenses. Only free one is code-size limited 

I'll be putting them to use as controllers for the FPGAs; communicating with a pool over ethernet and providing a remote interface. This will make the FPGAs completely independent, and far more stable than a GPU miner 

Only thing I'm missing are ethernet controllers. I'm looking at WIZnet W5100 breakout, but will have to wait until I've mined enough bitcoins to buy them 

P.S. Yes, I know the Altera C120 dev kit has an on-board ethernet controller. And no, I don't want to lose all my hair fighting SOPC system builder to get it working.

Sounds good to me. Basically what I meant by my second suggestion (after the EDIT).

I'd personally still have the option of tweeting your receiving address (with some special syntax). Seems easier to me, although perhaps less secure? *shrugs*

If I had that kind of hashing power, I'd go solo, just because it seems cooler to go solo  Plus you get transaction fees (tiny though they are)!

What miner are you using? Are you mining "solo" (connected to a bitcoin/bitcoind client on your local network) or are you mining as part of a pool?

If you've told your miners to connect to your local bitcoin/bitcoind client, then you should eventually see a "Generated" transaction show up, of the amount 50BTC or more. Those take 120 confirmations before they fully mature and show their final balance (may appear as a 0.00 transaction until then).

Do you mean 400,000 khash? I don't think there are any GPUs that get 4Ghash each.

A 400 Mhash/s GPU will generate a new block on average every 13 days, at the current difficulty. Divide that by the number of GPUs mining at 400 Mhash/s and you'll know the average time until you get your victorious 50 BTC.

Sure, if you can afford the steep cost of FPGAs.

I haven't much thought about an actual product, since I doubt anyone would buy it at the mhash/$ rate FPGAs get.

With regards to an eWallet being shutdown:

Imagine an eWallet website that published its entire database, up-to-date, for anyone to download. Only catch is, it's encrypted (e.g. AES). In case the servers get taken down, the data will likely still be floating around in the ether, ready for any one of the trusted admins to grab, decrypt, and reimburse users.

Yeah, I know, crazy idea.

I don't use Twitter often, but here's my stab at a method for implementing this:

*Assuming the thing is called TweetTip. Could be anything. Just to get the idea across...

Step 1) tweet "#tip @bob 1BTC" to the TweetTip account (as suggested)
Step 2) TweetTip tweets back with a unique Bitcoin Address and probably "@bob 1BTC" so you know what it's for.
Step 3) You send your BTC to that address.
Step 4) TweetTip confirms that it has received the amount with a tweet to you.
Step 5) TweetTip checks bob's recent tweets for a receiving address (as suggested).
Step 5a) If found, send BTC to that address. Tweet to bob that he got a tip from @you
Step 5b) If not found, tweet to bob he has Bitcoins waiting! Link to TweetTip.org/HowToGetYourTip
Step 5c) Periodically re-check bob's feed for receiving address up to a maximum time limit (90 days?)
Step 6) Profit


So ... is this possible with Twitter's available API? And if so, does that make the most sense?

The most complicated step is 2&3. If the official bitcoin client had bitcoin:// URI support that'd make things a bit easier. TweetTip could tweet "bitcoin://receivingaddress/btcamount" or whatever back and then it'd just be a matter of clicking and Accepting on the desktop client.

Anyway, thoughts? I'd be willing to take a stab at this if it sounds good to others.

EDIT: Or would this make more sense:

Step 1) Go to tweettip.org, type tiper's name, tipee's name, and amount.
Step 2) Send BTC to address that tweettip.org responds with.
Step 3) Once received and confirmed, TweetTip proceeds from Step 5 above.

Your card was OC'd too much, caught fire, and let the blue smoke out of your entire computer. Now how much do BTC cost you? (Full Capital Cost)

Okay, so you just spent >$1000USD to buy a new computer, since the last one caught on fire. What could you have spent that money on instead? Couldn't you have thrown it into the stock market? Or maybe community college classes so you can push for a raise next year? (Opportunity Cost)

Well you decided school is lame, and The Stock Market For Dummies is too expensive. So you spend a few hours picking out hardware, drop $1500 on a new system, and sit around doing nothing but fantasizing about your sweet new rig. (Lost Time)

New machine is here! You spend a few hours putting it together, lost a few fingernails, and sliced your finger open on the metal case. Now you can't donate blood tomorrow because you lost a pint of blood from that cut (Lost ... erm ... Blood?)

You spend a few hours tweaking the new cards, OCing them, etc. (Lost Time)

You spend every night lying awake at night watching the machine to make sure it doesn't go down. (Lost Time and Increased Healthcare Costs in the Future)

Next week, you refresh Mt. Gox for the millionth time and notice the curve dropping ... and dropping ... and now BTC are worth $0.05USD. (Risk)

And that, my friend, is why BTC are so expensive (or, actually, it's because the value of a currency isn't determined just by the cost of manufacturing it)

You didn't factor in Capital Cost (price of your mining rig) and all the other factors discussed on this forum before.

Post your command line.

Here's mine (on Windows. In linux I had to set DEVICE to 1), for a 5850:

phoenix -u blahblahblah DEVICE=0 VECTORS AGGRESSION=11 WORKSIZE=128 BFI_INT

You're not using phoenix correctly. FASTLOOP only works correctly for AGGRESSION < 8. Remove the FASTLOOP argument and retest.

EDIT: You also don't specify the worksize for phoenix. Not sure what that card needs (I'm guessing 128 by the poclbm command you posted).

Darn you phoenix! 

Thank you for posting the link! Great to watch! *applause for PLATO*

Part 2: http://www.youtube.com/watch?v=UuRys98OzlI

300 seems low. Are you using phoenix with BFI_INT?

I'm getting 320 MH/s on Windows at 850, SDK 2.3, phoenix 1.3. Linux was getting slightly better figures (when it wasn't crashing ...).

I haven't tried SDK 2.1 on Windows yet. That might bring me closer to grndzero's glorious 360 MH/s.  

Maybe. I tried ctrl+alt+backspace to no avail. Had to REISUB every time it locked up. The miner also stopped. I did not try SSH though. I might take another stab at getting Linux stable later.

Would an App Store, for PC applications (Windows, Linux, Mac), that accepts BTC make sense? I couldn't find any sites listed on the wiki that would allow someone to sell an application. There are a few file sharing sites where you can put a price on a file, but this doesn't handle Updates, Refunds, and Support.

Is this something that is in demand in any way? It would most likely be useful for little utilities, things that cost less than 2 maybe 3 BTC, where the low price would make PayPal or CC transactions difficult.

This is probably that block, by the way:

http://blockexplorer.com/b/120728

You should see your receiving address listed next to the "Generation" transaction.

Yes. The transaction that sent you (and the rest of the pool) money was included as part of the generated block, and so it isn't valid until that block matures. It takes 120 confirmations before a block matures.

In 113 more blocks, the Credit will change to 0.41. It shows as 0.00 until then.