[[Update] Alternate vendor: https://bitcointalk.org/index.php?topic=80005.msg890795#msg890795]

[Update] Alternate vendor:  https://bitcointalk.org/index.php?topic=80005.msg890795#msg890795


We are looking at potential of offering prepaid card which can be funded by selling Bitcoins.

Restrictions
1) The card MUST be registered. The card must be registered in order to reload it.  Card issuance and registration will be by 3rd party bank.  Normal KYC and AML requirements will apply (including full name and SSN).   When you receive the card you will use the bank's portal to register. Our company will have no access to this information.  If you do not register the card it will continue to function but you will be unable to reload it until registered.

2) You sell coins, we buy them, and as a result we owe you USD.  That debt in USD will be settled by loading your prepaid card.  Selling price will be based on MtGox prices minus a spread of 1% to 2%.  We won't be able to accept Mt.Gox (or other exchange) codes or facilitate trading between peers (exchange).  Trades will always be only one way.    These aren't our ideas and are required to implement them if we wish to secure a license and merchant account. The load/reload will be a cash deposit to your account.  That means your funds will be available (almost) instantly.

3) There will be fees.  The majority of these fees go directly to the bank and interchange network.  Our compensation will be primarily* based on the spread between rate we purchase coins at and the rate we can sell them to the major exchanges.   Our goal is for that spread to be 1% to 2% but will float dynamically based on our available cash reserves.   Consumers will know in advance what rate they are selling coins at.  *In the name of full disclosure we do receive a small payment from the network for each card sold and each load performed but we are prohibited from discounting or disclosing it.

4) Offer will be for US residents only.

Tentative fee schedule
Card issuance:  ~$5.00 (plus S&H)*
Reload: ~$3.00 **
Monthly: ~$3.00
ATM Cash Withdrawal: ~$1.00
ATM Balance Inquiry: ~$1.00
ATM Decline: ~$1.00

POS Signature Purchase: FREE
POS PIN Purchase: FREE
"Cash Back" on PIN Purchase: FREE
Lost Card Replacement: FREE ***
24/7 Phone Customer Service: FREE
Employer Direct Deposit: FREE

* We can provide account details (card #, exp date, etc) however you will be unable to reload until you receive the physical card and register it with the bank.

** Reloads are possible via Bitcoin sales and ~10,000 POS locations (no they don't take Bitcoin, only USD).  The network is significantly smaller than GreenDot or NetSpend but should be useful for loading some emergency cash.

***Card replacement at no cost is for first replacement and by USPS First class mail only.  Subsequent replacements or overnight delivery has higher fee.

Loading Limits
Max Initial load: $500 (unregistered)
Max reload per tx: $1,000 (requires registration)
Max reload per day: $1,000
Max value per card: $5,000

[Update] Alternate vendor:  https://bitcointalk.org/index.php?topic=80005.msg890795#msg890795

http://www.networksolutions.com/whois-search/retweetforcoins.com

The contact data isn't shown here because it is in privacy lock but the registrar just contacted me (automated) and provided registration details and it has my name, address, email, phone for contact. 

Same for:
retweetforcoins.com
tweetforcoins.com
retweet4bitcoin.com
twitterbitcoin.com

and a dozen more.

Thought I would post here as the real owner may be a bitcointalk user.

Should I be worried?  Or should the real owner be worried?  I guess if I was malicious I could use the registration information to seize control of the domains.

Anyone else sees massive delays.

It use to be 1-2 hours, then it turned into a couple hours, then a lot of hours but usually the same day.  My most recent tx was 3 days ago and hasn't shown up in Dwolla.  

Mt.Gox customer support is clueless as usual.  Anyone else having problem?

Hey Mt.Gox here is an idea if you DON'T HAVE THE FUNDS TO ALLOW A DWOLLA WITHDRAWAL ..... DRUMROLL .... DON'T FUCKING OFFER A DWOLLA WITHDRAWAL!

I would rather see "no funds available for Dwolla withdrawal.  Estimated delays 3-5 days" than a "withdrawal" button which does nothing and keeps my funds locked up in limbo.

See new thread: https://bitcointalk.org/index.php?topic=82924

If you currently are using prepaid cellphone/wireless/mobile broadband or planning to in the future would you be interested in a service which provides pin codes and RTR (real time recharge directly to phone #) paid for with Bitcoins?

Would you honestly use such a service?  
What if 1% of purchase price was donated to Bitcoin open source development team?
Prices would be slightly below retail (i.e. $50 prepaid PIN or RTR would be $48 to $49 equivalent in BTC)?

Pin codes would need block confirmation(s) but I think the risk of double spend is low enough on RTR to have them processed 0-confirm.

Interested? Comments?

Taking a look at BFL waterblock images:




And the naked PCB images:


My guess is that the 12VDC to 1.2VDC PSU is located on the right hand side of the board (the set of black squares).
Is that correct?

We know from GPU cooling that the VRM end up producing significant heat.  Just want to make sure the BFL power supply is directly under the water flow.

[The Purpose (also know as "are you fraking crazy FPGA are going to take over the world ... ")]

So the original thread is here (but the plan changed a lot and the thread got sidetracked at points w/ flames & trolls)
https://bitcointalk.org/index.php?topic=66606.0

The Purpose (also know as "are you fraking crazy FPGA are going to take over the world ... ")
I ALREADY have a farm of six 3x5970 rigs plus another 6x 5970s cards looking for a home.  The hardware has long since been paid off and I have some measure of pride knowing the rigs I built are just about as efficient as is possible with GPU tech (although some optimizes 7970 rigs might edge them out).  The goal is to extend that investment as long as possible.  Kinda a GPU "last stand" against the encroaching FPGA hoards  

My goal was to find a way to:
a) survive the summer without the 1/3rd increase in electrical cost
b) avoid paying ~$3K to the upgrade AC system (farm was expanded in the fall so current AC won't be able to handle it)
c) have fun building a big insane system.
d) see if it would be possible to capture some of that heat for preheating hot water heater and/or heating the house.

So I had this crazy idea.  Can you put 24+ HD 5970s in a standard server rack and using a really powerful pump move all that heat (18,000 BTUs) outside?

Well the farm is 50% converted.

The Rack
From top to bottom is APC PDU, management server, gigabit switch, second APC PDU, and the first three water cooled rigs.


Closeup of the rigs
No I am not cooling it with milk.  I guess the flash made it look like that.  Just using plain distilled water.


Connectivity & Power
I need some better cable management but power on left, connectivity on the right is a good start.  I hope to eventually replace all the flash drives with PXE.


Manifold
First three rigs are hooked to the three left most ports.  Isolation valves on top, flow control valves on bottom.
The connected loop on the right ensures even if I absent mindedly disconnect all 3 rigs the pumps will still get about 1gpm flow (important to keep the pump cool).  The photo is kinda hard to tell but this is mounted on the right hand side of the rack when looking from the POV of the first photo.
http://i.minus.com/iBLM12pskhT2g.png

The pump
A real monster but quiet and has a nearly silent fan in the back which reduces the amount of heat which ends up in the loop.  A pair of unions simplify hooking it up to the loop. The pump and fan are the only component which can't run on 240 which necessitates running 120V extension cord.


The radiator
Has about 16x the pipe surface area as your "normal" 3x120mm radiator and about 6x the fin surface area.     I am still using the poly tubing but will be replacing it with PEX when I get the time.  Fan is just a "normal" floor fan.  Probably 1800 cfm.  I may replace it with a car radiator fan or maybe just a outdoor rated workspace fan.



The rack contains:
3x quad 5970s rigs
2x APC 9571 PDU (240V, 30A, 80% derate) for 11.5 KW usable power
1x Cisco 24 port gigabit switch
1x 1U watchdog server (runs bitcoind, p2pool, remote power relay card, and monitoring software)

Current config:
12 5970s (24 GPUs) ~ 9.2 GH/s

When complete:  
24 5970s (48 GPUs) ~ 18-20 GH/s

Theoretical max:
40 5970s (80 GPUs) ~ 30-32 GH/s

Anyone know of any API to get Mt.Gox daily price information for Bitcoin?

There is:
http://bitcoincharts.com/t/trades.csv?symbol=mtgoxUSD&start=1315906316

but it returns every trade.

I just need daily price.  Would prefer volume weighted average price but opening price, closing price, simple avg price, just about anything on a daily basis would work

Something like this but for BTC:USD
http://www.google.com/finance/historical?q=NASDAQ:AAPL&authuser=0

[Proposal:]

Proposal:
A patch to bitcoind that modifies tx list returned by getmemorypool by excluding tx below a user defined fee.

Background:
The getmemorypool RPC call returns the components necessary to build a block header.

version" : block version
"previousblockhash" : hash of current highest block
"transactions" : contents of non-coinbase transactions that should be included in the next block
"coinbasevalue" : maximum allowable input to coinbase transaction, including the generation award and transaction fees
"time" : timestamp appropriate for next block
"bits" : compressed target of next block

https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_calls_list

The getmemorypool RPC call is used by p2pool to generate blockheaders for getwork requests by miners.  The default action of "getmemorypool" is to return all valid tx not yet known by the node to be in a block. I am seeking development of a patch which will exclude transactions with a transaction fee below the min fee set by the operator.  The list of tx returned should simply be the tx with an appropriate fee.

Implementation:
I imagine the easiest way to accomplish this is to have a new RPC call "setminfee".  By default "setminfee" is set to 0 BTC.  The modified "getmemorypool" would check the min-fee value (default 0) and exclude any tx with fee < min fee.  I am open to alternative implementation however a reason should be provided.

Bounty:
Make me an offer.  Honestly I have no idea the amount of work this will involve.  I don't want to vastly overpay or insult anyone with a low ball offer.

I need the specs on BFL power adapter.

Updated w/ specs as I know them.
Polarity: Center 12V
Inner diameter of barrel connector: 2.5mm
Outer diameter of barrel connector: 5.5mm
Barrel length: 12mm
Max DC amperage:  10A @ 12V (PSU is rated for 120W.  BFL care to comment on actual max DC load of a BFL Single)

Has BFL provided any specs?  
Anyone look on their Power Supply some or all of that might be listed?
Any photos of the PSU available?

On edit:
link to BFL post on physical specs:
https://bitcointalk.org/index.php?topic=65752.msg773989#msg773989

On one of my rigs I kept noticing the same GPU (#4 grr) going DEAD.  I lowered the clock, dead, lowered clock, dead. Finally put it at only 750 Mhz it was fine for a couple days and then I noticed it dead again.

I verified it now is no longer stable @ even 750.   Three "dead"s in 24 hours.  I dropped it to 725 (stock) and it has been stable for almost a day now (will update post for longer periods of testing).  So far just that one core on one rig (1 of 48 gpus) dislikes even moderate overclock.  The other GPU on the same card is fine @ 800 MHz.  At higher overclocks the "bad core" dies almost instantly.  Those two facts and a 1200W single rail PSU design make me think it isn't a power issue.

This is a very old card (over a year old need to lookup sales date).  It was one of the first 5970s I bought, and it is what convinced me to replace all my other GPUs with 5970s to consolidate my growing farm.  It has never been overvolted but last summer it did run "hot" for about a month before I bought a mini-split system to supplement the house main AC.  It has run overclocked but nothing crazy.  I ran it (guestimates) 835 early on.  I dropped all the clocks to 820 and then 800 once I got up to 6 rigs because micro managing them became a hassle.   I can't try overvolting at this point (which can "restore" performance on circuits suffer electromigration) because it is in a Linux rig.

Other than 3 fan failures (and me dropping a motherboard down the stairs) this is the first casualty of mining I have had.   As our GPUs get older I wonder if anyone else has noticed something similar.

[Background (can safely skip if TL/DR)]

Background (can safely skip if TL/DR):

on edit: removed as it seems to be a distraction.

..


Remote out of band power control
There are PDU that offer ability to power cycle devices remotely but they tend to be very expensive and have insufficient wattage for a large number of rigs.  For example the unit in the link below has 16 individually switched outlets but only 5.76 KW of switchable power or about $100 per KW.  Using conventional remote power solutions is cost prohibitive. 
http://www.amazon.com/Tripp-Lite-PDUMH30HVNET-Distribution-Switching/dp/B0013HY9E2

So why not just shutdown/reboot the rig via the command line using ssh?  That certainly is a solution most of the time but the rig may be unresponsive, the mining software may hang when it tries to shutdown with crashed GPUs, or rig may hang during reboot.

An analog power switch is essentially fool proof.  Power rig off, wait, power rig on.  It can't be defeated by failing software on the mining rig. I am gauging interest (no guarantees, no pre-orders, no timelines just gauging interest) for a control board which would provide remote out of band power control for multiple mining rigs.

Tentative simplified board specs:

• Requires a host "server" (any non mining computer) with an RS-232 port (USB to RS-232 adapters are available for ~$10)
• Can physically power on, power off, and power cycle up to 8 rigs (multiple boards could be used to control more rigs)
• Linux and windows OS supported.
• Will expose an API for integration into existing or custom applications (like hypothetically ANUBIS)

Cost: ~$100 (rough estimate)

Finally got it stable and hashing.  It was brutal trying to get 4x5970 working in Linux.  Sadly BAMT doesn't work (no dice for 8 GPU in 32bit kernel).  I tried xubuntu but hosed something up installing SDK 2.1.  Tried to restore from an image I made and it wouldn't boot.  Ended up grabbing LinuxCoin (x64) and dropping in cgminer.  I don't like it but it works for now.

Code:

  cgminer version 2.3.1 - Started: [2012-02-28 12:30:03]
--------------------------------------------------------------------------------
 (5s):2935.9 (avg):2952.6 Mh/s | Q:11590  A:3272  R:57  HW:0  E:28%  U:15.06/m
 TQ: 8  ST: 9  SS: 26  DW: 1950  NB: 17  LW: 15248  GF: 0  RF: 0
 Connected to http://192.168.0.189:9332 with LP as user user
 Block: 000007200ebc4183c7cefd4ed93eea81...  Started: [16:04:46]
--------------------------------------------------------------------------------
 [P]ool management [G]PU management [S]ettings [D]isplay options [Q]uit
 GPU 0:  52.0C  960RPM | 378.0/378.7Mh/s | A:445 R: 7 HW:0 U: 2.05/m I: 8
 GPU 1:  52.5C  960RPM | 378.0/378.7Mh/s | A:399 R:10 HW:0 U: 1.84/m I: 8
 GPU 2:  49.0C  960RPM | 378.1/378.7Mh/s | A:431 R: 4 HW:0 U: 1.98/m I: 8
 GPU 3:  54.0C  960RPM | 378.0/378.7Mh/s | A:403 R: 3 HW:0 U: 1.85/m I: 8
 GPU 4:  59.0C  960RPM | 352.8/353.3Mh/s | A:396 R:10 HW:0 U: 1.82/m I: 8
 GPU 5:  58.0C  960RPM | 378.0/378.6Mh/s | A:407 R: 9 HW:0 U: 1.87/m I: 8
 GPU 6:  55.0C  960RPM | 378.1/378.6Mh/s | A:413 R: 8 HW:0 U: 1.90/m I: 8
 GPU 7:  53.5C  960RPM | 327.8/328.2Mh/s | A:378 R: 6 HW:0 U: 1.74/m I: 8
--------------------------------------------------------------------------------

Clocks are somewhat conservative but it is running @ ~3GH/s and pulling 1112W at the wall (120V).  Once it is stable it will move to the 240V PDU so it should be 20-25W less there.  One of the eight cores wouldn't clock to 835 (went sick 0Mh/s instantly) since I was tired I just left it @ 750 Mhz for right now.  It is pointed at p2pool which makes share count, U, etc "weird" due to dynamic share difficulty.

Total System Load: 1112W
Total System Hashing Rate: :2.95 GH/s
System efficiency: 2.67 MH/W
Measured (not calculated) no-GPU (not even installed in rig) system idle: 190W
GPU AC load:  230W ea
GPU DC load: ~200W ea
Total System thermal load on water loop: 800W
GPU efficiency: 3.21 MH/W.  

On edit: old pic removed (better pics below)

Note:
I don't have 30GH/s the figure comes from the potential.  3GH/s per 4U.  45U in a rack.  1U for switch, 2U for PDUs, 2U for "watchdog" server leaves enough space for 10 4U rigs.  

I am getting notification that an address ins't part of the chain despite it having 63 confirmations and showing in both blockexplorer and blockchain.info.

The reason I ask is because it looks like Bitcoin is becoming more decentralized.

http://blockchain.info/pools?timespan=14days

I remember when there was fear Deepbit alone would go >50%.  
Then it was Deepbit + Slush > 50%.  
Then Deepbit + Slush + BTC Guild >50%.
Now we are getting close to top 4 combined being <50%.

If p2pool (and smaller pools) could pull another 500 MH/s from the big 4 then even the top 5 combined wouldn't be 50%.  

Just interested what other people run at.

Select only 1 fan choice & 1 temp choice.

If you use auto-fan or some dynamic fan put in what you average fan speed is (estimate if you need).
If your GPU temps vary put in the upper range of what you are comfortable with them running 24/7.

For some of us temps in summer are higher than in winter put what you are comfortable with.  For me I keep GPU <80C.  Sometimes they are much lower than 80C (like February in the garage) but I voted for 80C.

Bulanula thread was inspiration.  Discussion on GPU temps and longevity.
https://bitcointalk.org/index.php?topic=62801.0

Tried to transfer out some BTC from Mt. Gox.

Strangely it gave me a tx ID of : d7fa70f6-26be-43a9-9c97-ee83f8d9d399

Never seen Tx Id with dashes

Blockchain info & Block explorer say Tx ID doesn't exist and the address in question shows no transaction being received. Blockchain.info is pretty good at showing even unconfirmed transactions.  Note: this isn't a wallet issue the network is showing the transaction simply doesn't exist (nor is there any other transaction for the amount to the address).

On edit: 8 blocks (100 minutes) have passed and transaction is not on even unconfirmed on the network.  

On edit edit:  looks like for Mt Gox to Mt Gox transfers the transfer happens internally and later (much later ? ) rebalanced on the block chain.

Locking.

On edit:
Good catch by Krin.  The coupon code "SEASONIC15" is good for any SeaSonic PSU not just the 1250W monster below (although lets be honest you know you want 1.25 KW of GPU powering goodness).

http://promotions.newegg.com/PS/028812/index.html

Original post
------------------



80-Plus Gold
Fully Modular
Seasonic build quality
monster 1250W
Single giant 104A (1248W) 12V Rail
91% efficiency @ 50% load and 88% efficiency at 100% load (yes 1250W)


Use promo code "SEASONIC15" at checkout.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817151109


80-Plus certification report:
http://www.plugloadsolutions.com/psu_reports/SEA%20SONIC_SS-1250XM_ECOS%202811_1250W_Report.pdf

Technically it is a loan but may be interested to those contracting for hashing power.

https://bitcointalk.org/index.php?topic=62189.0

Instead of hashing rate & time being fixed the amount repaid if fixed (set by you).

There is no variance in amount generated just in the time taken.  Looking for 100 BTC.  You set amount to be paid out.

[I would like to arrange a loan of 100 BTC where I direct the output of my hashing power to a repayment address until repaid in full.]

I locked in a deal on some GPUs and I am 100 BTC short.  Dwolla is going to take 3 days to fund and I would rather lock this up right now.  It seems silly to transfer fiat knowing that in 2 weeks I would have the funds generated by mining anyways.

I would like to arrange a loan of 100 BTC where I direct the output of my hashing power to a repayment address until repaid in full.

I have ~9.5GH/s online so that should be repaid in ~ 2 weeks.  Actual repayment may vary slightly based on luck.  I would prefer to use my current pool (Bitminter) as I trust the operator.  I use ABC Pool as a backup.  I will setup your repayment address there too.  If you want an alternate pool we can arrange that.

I feel this is a relatively low risk/stress loan as repayment begins immediately.  Just to be absolutely clear.  This isn't a mining contract per say.  The amount repaid is fixed and the amount of times varies (where in mining contract time is fixed and repayment varies).

Just let me know the amount you wish to be repaid (i.e. if you want 3% interest it would be 103 BTC paid in full).  
Remember repayment is continual, will take roughly 2 weeks, and may vary slightly in length (but not amount) due to downtime & luck.