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1  Economy / Services / looking for 3D artist for blender scene on: November 15, 2016, 07:55:21 AM
Im looking for a 3D artist to provide a few renders or a (blender cycles) scene to show off some high end planters. The scene can be a modern garden or luxury apartment interior, it can be something you modeled earlier.

The planters themselves are very simple in geometry, I can provide plans and models, but the material is a bit more tricky: shiny and highly reflective messing, zinc and slightly translucent polyester. I can provide photo's.

The overall scene can be simple, with perhaps little more than some stone floor, grass, a wall and plants, but the result has to be absolutely photorealistic.

For reference, here is my own current, unfinished and totally unsatisfactory attempt in blender:

(in fairness, I was mostly learning blender and experimenting with particle systems etc doing this)

You can use something other than blender, if you have access to a higher end rendering engine, but I would prefer blender as it would allow me to render the scenes myself.

If you are interested, show me some relevant examples of your work and give me a price estimate.

2  Bitcoin / Project Development / ANN: 100mBTC (0.1 BTC) physical coins + 5 free coins naming competition on: April 22, 2013, 09:07:46 AM
HI all,

Im happy to (pre) announce that in about 2 months I intend to start selling 100mBTC physical bitcoins. Im about to place the orders for the minting and the hologram design will be finalized in the next weeks.  Im posting this here to make you aware and gather some feedback before I pull the trigger.

These coins will be made in beautiful  bi-metal, just like 1 and 2 euro coins and be a bit thicker and heavier than Casascius coins. This is the almost final design of the front:

Feedback is welcome, but its unlikely I will change a lot.

The back will use the same principle as Casascius, with a fully custom tamper proof holographic adhesive covering the private key, while a window on the hologram will reveal the public key, possibly as QR code.

The reason I decided to go ahead with this is not so much to give casascius competition (I have the greatest respect for him and I am the proud owner of a fair number of his coins), its just that I used to hand out 1BTC coins as freebees, but at the current price, even Casascius new 500mBTC coins are rather expensive conversation starters.

Initially I planned to make these coins as cheaply as possible; using cheap aluminum and stock hologram seals with only a lasered public key on the holograph, but it would make counterfitting just too easy. Since most of the costs are NRE and the per coin price is rather low, I figured it should be possible to sell enough to enable beautiful and secure (*) coins that are still affordable enough to hand out. The NRE to mint the coins and produce the hologram is quite substantial, so I have yet to decide on pricing, but Im aiming for as close to face value as possible, particularly for large orders I hope to get the price (excl bitcoin value) in the single digit euro range. This wont make me rich, but for now Ill be happy to just recover the investment.

(*) About security; Ive looked at this from all angles, Ive considered doing 2 factor, but in the end Ive come to the same conclusion as Mike: its just not feasible for small denominations. So buyers will have to trust me that I dont keep copies of the private key and I wont steal their coins. Im banking on the reputation I hope to have among many here that used to trust me with their hashrate, and hoping the smaller denomination and small markup price - making it more likely they will actually be redeemed-,  will make that pill easier to swallow.

I intend to sell these coins directly for BTC but also for a higher premium through ebay and bitmit. On ebay these coins will also be sold for paypal; but will ship without BTC value until the buyer confirms reception. I hope that will provide me with sufficient protection against charge backs. Any knowledgeable feedback on this would be appreciated.

One thing I havent decided upon is a name. I still have a company that my brother and I registered a few decades ago  which was called Foresee. We will likely put this bitcoin business under that legal umbrella, so using that name is one option. But if you have any better suggestions, please PM me your suggestion. If I decide to use your name, I will gladly send you 5 free 100mBTC coins as thank you. Submissions should be sent within a week from now.

I will probably do formal preorders later, once I have a firm shipping date,  but to get a feel for the volume and amount of (dis)trust I have among forum members here, I would also appreciate if you posted a non binding "preorder" below indicating how many coins, if any, you would be willing to buy. Doing so will entitle you to a small discount once these coins  go for sale provided you actually do place the order.


3  Economy / Service Discussion / Pirate accomplices on: August 27, 2012, 07:34:12 AM
Pirate's scheme from the getgo had all the hallmarks of a typical ponzi.  Without more information than what was and is known publicly, anyone who can think should and would have assumed it to be a ponzi.

The only reason I gave this scheme any credibility whatsoever was the fact that a lot of generally intelligent and (apparently at least ) even honest long timers on this forum gave it not only the benefit of the doubt, but full credibility. Many of them did know more than I did, because they met Pirate, because some at least claimed to know and understand his business model.  People who I assume to be smart enough to recognize a ponzi when staring at one this obvious. If they were totally convinced it wasn't one, what was it they knew that I did not?

This is still true today, perhaps even more so than 6 months ago. IF 6 months ago, I was 95% sure  it was a ponzi, right now, ironically,  I am *less * sure . Why ? Because these same, generally intelligent people  dont seem to be thrown off one bit, despite the fact that it looks like a ponzi now more than anything ever could.  Because I dont believe Matthew, crazy as he may be, is actually stupid enough or can even afford to bet $1M on something he wouldnt be sure off or doesnt  understand himself.  Because none of those big Pirate backers are getting out their pitchforks. In fact most of them are still tacitly supporting him.

There are not so many explications for this. Either it is not a ponzi and somehow Pirate will pay up, crazy as that may sound to anyone who has no more information than I have.

Or if it is a ponzi, then the vast majority of pirate backers were given an incentive to pretend to believe him. I might believe Goat is stupid enough to be fooled  by pirate, but I will not believe that from most of the others. IOW, if this unfolds like it appears it will,  they would be knowing accomplices.  And very effective ones at that.
4  Bitcoin / Development & Technical Discussion / transaction timestamp in bitcoin-qt on: August 19, 2012, 06:12:42 AM
Why does bitcoin-qt show transaction time stamps as the time it received/processed the block rather than the time the transaction happened?

Now if you turn your PC off for the weekend, and back on monday, all transaction that occurred over the weekend will seem to have occured on monday morning around 8 am :S I would so much rather see when the transaction actually took place, even if its just an estimate.

5  Other / Off-topic / Any other (Koi) ponders here? on: July 25, 2012, 12:28:20 PM
I thought Id leave this here.

My house had a large (~50K liter) old and neglected pond, that looked like this:

Its rather nice, but the water was clear as mud. There were supposedly some fish in there, but you wouldnt be able to spot the Lochness monster  Smiley

I decided to clean it up last year.  A hellish work I tell you.

And to prevent it from becoming a mud pond again, I wanted some filters. Pond filters for a pond this size are exuberantly expensive, think more expensive than a small car, so I built a cheap DIY bio filter from plain rain barrels and some plumbing material.

Not exactly pretty, but I hid it well out of sight.

I didnt expect it to turn the pond in to a crystal clear aquarium, the pond is surrounded by trees, and really, from everything I read, I would need at least 3-4x more barrels for a pond this size.  I would have been content just being able to spot my fish, but the results surpassed my expectations.

This is the result one year later, pics taken this morning; granted, its not an aquarium, I have certainly seen more clear water, and the water has a green/yellow tan, but boy am I happy with it!

6  Bitcoin / Mining / [ANN] Puppet Master. Earn (much) more than 110% PPS. on: June 26, 2012, 03:54:23 PM
ASIC mining is almost upon us. For many of us, myself included, that will mean the end of our bitcoin mining careers.  If you have somewhere between 0.5 and 5 GH and you want to max out your GPU or FPGA mining revenue over the few months we still have left, this thread is for you.

Proudly announcing one of bitcoins worst kept secrets:

What is Puppet Master?
Puppet Master is pool hopping done right. No proxy. No bullshit. No crumbs.
Traditional hopping proxies like Project 2, ABC, Project X, Clipse's bonus pool etc are easy to use and allow a miner to earn a little over 100% PPS; but they all suffer from some serious drawbacks: a proxy causes stability and scalability problems, generally high reject rates and it provides no transparency in either generated profits, or where the hashing power is sent to. Current hopping proxies are also paying just crumbs, some even charge you for the privilege, others hold your coins ransom for a week.

Puppet Master does away with all that, and uses no proxy. Instead it relies on cgminer's API. The Puppet Master software runs on my servers and analyzes the blockchain and pools and decides which pool is most optimal, then sends a command to the "puppets", ie miners, to hop there using cgminers built-in API. While this is more complex to configure and manage, the advantages of this approach compared to a proxy are legion:

- Your miners are connected directly to the pools using your own accounts. You are always in control of your payouts, you dont rely on me to send you your coins.
- Total transparency. You see where is being mined, you can see how much it really earns. Hint: its more than 110%.
- You choose were to mine when we have no pool to hop. You can use p2pool, or any PPLNS, PPS or DMG pool of your choosing.  
- No extra stales and rejects.
- No single point of failure. Even if Puppet Master would fail and the service would be disrupted, about the worst that can happen is that your miners stop hopping and instead mine the same pool. They will never idle.
- GPUmax integration.  If you have a GPUmax account and API key, Puppet Master will detect when GPUmax is running public work and at what price, and adjusts the hopping strategy to maximize your profits without compromising your GPUmax rewards. You will only hop as long as expected hopping revenue exceeds your GPUmax revenue, so Puppet Master will seamlessly combine GPUmax and pool hopping rewards, giving you the best of both worlds. Optionally, puppetmaster can also assist you in configuring an optimal GPUmax lease price.
- You get a simple but functional webinterface where you see your miners, hashrate, GPU temperatures, GPUmax status, pool statistics etc.

How much does it earn?
I cant predict the future, so I cant predict exactly how much you will make; Puppet Master users are subject to variance,  but it will certainly earn you more than you earn without puppet master and when averaged over a long enough time, substantially more than the other 110% proxy pools. How much more depends on how much public work GPUmax offers (and at what price), how long it will take for some of the hoppable pools to  switch payout schemes, and just plain luck. I dont give any guarantee, but historically, Puppet Master has generated  ~130% PPS without gpumax public work, and well over 150% during public work. I wont lie, as more pools are (finally) switching to hop proof payout schemes, these numbers are likely to go down, but people saying pool hopping is dead already, are not telling truth, do not know what they are talking about, or dont know how to do it properly Smiley.

How much does it cost?
Hopping proxies earn money on the difference between their actual revenue and what they pay you. As a miner, you cant see how much that difference is, so it may sound better to get a 110% payout than paying a fee (even if that 110% turns out to be 105% after stales and downtime), but the truth is you might be paying 20% or more to the pool op if he knows what he is doing.

Puppet master isnt free either; there is fixed 5% fee, and a sign-up fee/guarantee. The 5% fee is collected automatically by directing your miners to a dedicated worker for 5% of the time. You can monitor this precisely, its completely transparent.  BTW, this 5% may be lowered in the future at my discretion if our profitability is compromised by pools switching to honest payout schemes.

The signup guarantee is 5 BTC per user, but half this amount will be refunded immediately once you start mining with Puppet Master, the other half will be credited in its entirety to your fee balance, so you wont pay any % until you have mined ~50 BTC.

IOW, if you actually use Puppet Master, the sign up cost is zero.

The reason for this guarantee  is just to avoid me wasting a lot of time  with people just signing up to check it out without any intention of ever actually using it.  This fee is not refundable in principle, but I like to think of myself as a reasonable person, so if there is a good reason to, I wont hesitate to decide to refund anyone on a case by case basis.  Should puppet master cease operation, I will also refund any balance you still have. Im not demanding 5BTC to make money, its just to save myself a lot of unnecessary work and time.

What do I need?
For now Im only accepting users with more than  ~0.5GH and up to ~5GH for gpumax users. Less than 500MH is more trouble than its worth, more than 5GH can cause load balancing issues at gpumax particularly when avoiding gpumax passthrough. If you have more than 5GH and do not have a gpumax account, contact me.

You need either a static IP, or a hostname alias provider like You also need to use cgminer (2.3 or higher), you need full control over your network and firewall and you need to have some basic skills to set up cgminer and port forwarding.  Having a gpumax account will obviously increase your profitability, but is not required.  In fact, if you do not have a gpumax account, puppet master will give your mining revenue a bigger boost than for a gpumax user, who is already earning well over 100%. Well, used to anyway.

Using linux on your miners is recommended, particularly if you want to disable privileged API access, see below.

You need access to my cgminer API, does that mean you can control my GPU settings using  that API?
With the standard cgminer, in theory, yes.  As of cgminer 2.5, this is no longer a concern. api-groups lets you define which commands you give puppetmaster access to, and it only needs pool related commands. Instructions will be provided if you sign up. If you use an older version of cgminer, its possible to recompile with some minor changes to avoid giving api access to commands ppm doesnt need.

FPGA users have nothing to worry about and should just use the standard cgminer. AFAIK, there isnt any cgminer setting I could abuse when you use an FPGA.

Do you guarantee x,y or z.. ?
No. Im running this on a best effort basis. I dont guarantee anything other than whats been said. Not profits, not uptime, not hopping accuracy. However, puppet master is not new; as many of you know, it  has been operating for almost 6 months now, serving ~100GH for a number of users that were invited.  None of those users have come forward to the forums claiming I tried to steal their coins or kill their videocards, in fact, so far none of them have even stopped using it; every single person who has ever tried Puppet Master, is still using it today, so I guess it cant be all that bad Smiley.  You can also thank those users for helping me iron out the bugs, so you dont have to suffer them.

As for reliability, particularly over the last few months Im pretty sure we achieved over 99% uptime as I believe we have had only 2? unplanned outages that lasted more than an hour. And remember, an outage simply means you stop hopping, not that you stop mining.

Arent you a hypocrite, I thought you were against pool hopping?
Im not. I know some people have claimed I was crusading against hoppers, but if you read what I actually wrote you will find nothing of the sort. To illustrate, most of you will know Im not Goat's biggest fan, but if you go read Goat's project 2 thread, you will not see a single post of me criticizing him for doing what he did (well, other than ridiculing his utter failure to execute) for the simple reason that he was open and honest about it. I did rant against proxies that hop with their users hashrate without telling their users, as I did rant against pools that falsify their stats under the false pretense of preventing hopping. But Ive never voiced any criticism about miners doing the mathematically sensible thing.

Why would I use Puppet Master and pay fees instead of using some free hopping program?
If you can set up and use BitHopper, maybe you should. But none of the apps Ive tried are anywhere near as good at hopping as puppet master. Aside from the issues and stales associated with a proxy (even a local one), they are also poorly integrated with GPUmax and for hopping they rely on delayed (/false) pool stats, long poll timing or scraping to guess a blocks origin. While I admire the efforts of the developers and Im sure these apps were awesome once upon a time when you could hop a dozen proportional pools, I found their hopping accuracy tends to vary between poor and appalling. Puppet Master uses its own mechanisms which are vastly more accurate than anything else I am aware off and this accuracy translates directly in to higher profits.

How do I sign up?
Send me a PM or email State your forum name and email,  aggregate hashrate, number of machines and whether or not you have a gpumax account and API key. I will already send you the (optional) instructions on how to recompile cgminer if you want to do that.  

Im provisioning a new server right now, once that is ready and has been tested (ETA less than a week from now), you will get an address where you can deposit the 5 BTC guarantee, after which you will get detailed instructions and templates on how to configure your miners, workers and network in order to use puppet master.  Once you have it configured, and I verified your settings,  you will receive a URL where you can monitor your rigs and you will start earning.

7  Economy / Computer hardware / FS: Club 3D 5850 reference, noisy fan, Europe on: June 26, 2012, 07:16:45 AM
I have a Club 3D 5850 reference card for sale. The fan needs greasing or replacement as its very noisy, but it still works

This card runs stable at 950Mhz @ default voltage, has never been overvolted, and never ran at more than 70C.

Comes with original box, DVI/VGA adaptor, but no other accessories.

Shipping from Belgium to anywhere in Europe. Using TNT/Kiala that costs 2BTC within Benelux, 3BTC within EU.

Accepting BTC offers only.
8  Economy / Economics / Clarke and Dawe - The European Crisis on: June 21, 2012, 12:10:14 PM
Priceless Smiley
9  Economy / Securities / RFC: virtual mining bond and toxic mining (betting against mining bonds) on: June 19, 2012, 12:40:17 PM
Hey all,

Im strongly convinced mining bonds on GLBSE are currently way overpriced;  the typical price for these bonds seems to be 12-18 months of coupon payouts (ie, mining revenue at current difficulty), which I think is totally absurd considering difficulty has been rising by ~8% monthly for the past 6 months, block reward is about to half and ASICs will probably arrive in the next 6 months. I cant see how these bonds will make a profit over the next ~12 months. Even at the current trend, so before the asic and block reward halving, difficulty is increasing faster than coupon payouts.

Since there is no obvious way to short these bonds, Im considering the following:

Set up a virtual mining bond that is not necessarily backed by any hashing power (I actually do have some, but thats besides the point). These bonds will pay coupons based on difficulty, like any other mining bond; I would sell these bonds at prices slightly below current mining bonds to make sure they are more attractive (or as I see it, less toxic) than the other bonds out there. Dividends will be paid out of my pocket and from the bitcoins raised from selling these bonds.

Yes, I know how that sounds, but this wouldnt be a ponzi scheme; I would keep enough BTC at hand to buy back my bonds at any point in case my bet goes wrong. If people dont trust me enough for that, I may even put that in escrow somewhere. Now I would obviously run the risk that prices for such bonds will not drop, or not fast enough to offset the coupon payments, so I could very well lose money on it, which is obviously okay, the whole point is that I am betting the other way. I would not issue more bonds than I can easily afford to buy back at a predefined price.

Bond holders would risk no more than they would with any other mining bond, they would only risk that difficulty will go up faster than they expected, causing their bonds  to lose value faster than dividends make up for. Any mining bond carries that same risk (which I estimate to be huge). The fact that this bond would not be backed by actual hashing power is no extra risk, when you buy a bond, you dont own the mining hardware anyway, its not a share.

Now I assume Im not the only one who believes that over the next ~12 months, these mining bonds will depreciate faster than coupon payments will compensate for, so I would also like to set up another asset where people can buy shares in this venture  (tentatively called Toxic Mining) . The capital raised from these shares would be used as collateral to issue more virtual mining bonds without creating extra risk to bond holders (the extra BTC from the share sale allow us to keep more BTC on hand to pay coupons or buy back bonds even if our bet goes the wrong way).

This asset would not make a profit and therefore not earn any dividends until our bet pans out and we can start buying back bonds at prices that are substantially lower than the original price + coupon payments, Investors in these shares will take the same risk I would, and therefore risk losing part of their investment, or potentially even all of it if something extremely unlikely happens (like difficulty decreasing by a factor 3 or so over the next 12 months) but they stand to earn substantially if we win our bet and difficulty explodes in the next 6 to 12 months.

This would also be a convenient way for miners to hedge their risk. If you are about to order ASICs, but are unsure if a large difficulty increases will kill your ROI, you could buy shares in this company to hedge against it.

Anyway, Im not much of a gambler, so I am not going to go all in on this, but im willing to put 100 or so BTC aside as guarantee for a first batch of virtual mining bonds to kickstart this; I would love to hear what other people think, both potential bond holder and share holders. I guess I could also use a hand formulating the contracts.
10  Other / Off-topic / not so smartphone on: June 15, 2012, 09:35:50 AM
My android phone died recently and while waiting for a new one to arrive, I got around with a borrowed one.
As it turns out; Im kind of impressed by it.
How would you like a 7 day battery life. Stunning sunlight readable e-ink display. Extremely rugged (ive seen it survive drops from third floor on concrete, a car driving over it and being taken in to a shower all without any damage). Thin and light like no other phone Ive ever had in my pocket. Best reception and voice call quality of any cell phone Ive ever tried so far.

Granted, its functionality is "somewhat" limited. As in, making and receiving calls and text messages and, well,  thats about it. You can buy it for $15 on ebay. Its the amazing motofone f3.

Im seriously considering keeping it (or getting something similar as I do miss bluetooth when Im in my car). Of course I regularly miss all the other goodies and functionality as well, but Im no longer sure I want all that functionality in my phone, which is always too small when you need the smarts, and too big, fragile and battery hungry when you dont. So Im left wondering if it wouldnt make more sense to get a ~5-7" tablet for all the other "smart" stuff.

Has anyone else gone back from a smartphone to a dumb phone?
11  Bitcoin / Mining support / Split tunnel VPN on windows on: April 21, 2012, 12:16:13 PM
I need some help with this.

Situation: some miner rigs running cgminer on windows are behind a firewall that cant be controlled. I need to access the API remotely, so get around the firewall. VPN seems like the obvious solution, however I dont want the getworks and longpolling etc to go over the VPN, only the API traffic.

From what I gather, this requires a split tunnel. This seems to be relatively straight forward to configure on linux, but does anyone have a clue how to do this with on windows? Im looking at OpenVPN but the documentation is a bit ... overwhelming and I dont see anything like what Id need.

Other suggestions besides VPN are welcome too. On linux Id try SSH reverse portforwarding, and in theory Putty should enable that on windows too, but I cant seem to make it work.
12  Economy / Auctions / [Auction] [Mining contract] 1 millions shares - 1 BTC start price on: April 19, 2012, 08:18:18 PM
I represent a consortium of miners who have combined (dare I say, pooled?) their hashing power and now for the first time, we offer some of our hashing power for sale publicly. This first public 1M share auction is a test for us, and if successful, there may be many more similar, bigger and smaller contracts auctioned off, either here or on Bitmit.

Buyer will receive  1 million bitcoin difficulty 1 shares delivered to any pool he choses.

Delivery will begin no sooner than 26/04 and will be completed within 7 days (note, difficulty will change on the 26th).

Starting price for this auction is 1 BTC, bid increments will be 0.1 BTC minimum

This auction ends on Monday the 23th at midnight (UTC), or one hour after the highest bid was posted, whichever is later (to avoid ebay style sniping), but no later than 12hr after the original closing time.

Highest bidder is expected to pay the full amount up front within 48 hours of winning the auction.

Some questions you may have:

- Can this be delivered at *any* pool? P2pool? 110% proxy pools? GPUmax?
In principle, yes, assuming the pool is functional, can handle the load and you can provide us with several valid worker credentials.
If you want your shares delivered at P2Pool, you wont get 1M shares, since they are not difficulty 1 shares, but if we can work out the equivalent, then we can mine at p2pool (if you provide the workers).

- Can this be used for poolhopping?
Probably not. All 1M shares will be delivered to the same pool and we only guarantee you will receive your 1M shares within the 1 week time frame, we dont guarantee a minimum or constant mining speed or more precise timing.

- Can you guarantee delivery on time?
Yes. 1M shares per week is only a small fraction of our combined hashing power, we intend to run multiple such contracts concurrently in the future.

- Do you accept escrow payment?
A mutually agreed escrow service is acceptable, but the escrowing costs are for the buyer.

- Is this contract for 1M accepted shares?
No. The contract is for 1M shares, including rejects. Because we dont know what pool you will want these delivered to, we can not assume the risk of unusual high reject rates at some obscure pool. However, if the pool is working properly, you will not see more rejects than usual.

- How will you handle unexpected problems, like pool issues or other disputes?
Like adults and in good faith.  In principle the payment is non refundable, but if for some reason the contract can not be fulfilled in time, because the pool is down or for other unforeseen circumstances we will either agree to change pools, change dates or refund you pro rata the amount of delivered shares. We are reasonable, and our goal is just to be paid for our shares, not to profit from contractual loop holes. We expect the same from the buyer.

- I'm a miner, can I join this consortium?
Not at this point.

13  Other / Off-topic / PHP array question on: February 25, 2012, 10:32:34 AM
Im struggling with PHP to get data from a mysql db and put it in to PHP arrays in a way thats actually easy to use.

Assume I have a table "miners'" with the following fields:

ip (also primary key)

I want to fetch this from mysql, put in an array and then loop through all miners, in this example just to display the ip and names.

The best Ive come up with is this:

  $query = "SELECT * FROM miners";
    $result = mysql_query($query) or die(mysql_error());
    while ($r = mysql_fetch_assoc($result)) {
    foreach ($miner as $i=>$d) {
        echo "miner :  ". $d["ip"] ." ". $d["name"] .$d["whateverotherfield"];

I does work, but its such a kludge.
Im sure there is a better way, but I just dont see it.

Any help appreciated.

14  Bitcoin / Bitcoin Discussion / Truthout on: February 15, 2012, 05:48:23 PM
I sent an email to, asking if they wouldnt accept bitcoin so I could make an anonymous donation. I got this reply:

Thank you for supporting Truthout!  Per your email, we do not currently have a bitcoin account but this is something we will look in to.  If you would still like to make an anonymous donation, please consider calling in to us, 213-489-1971, and I can process a donation from you with just your credit card information so the donation can be completely anonymous.
Thanks again for your support.  We truly appreciate you!

Completely anonymous credit card transactions  Roll Eyes
15  Economy / Speculation / WTH? Someone playing ping pong? on: February 12, 2012, 12:12:17 PM
16  Other / CPU/GPU Bitcoin mining hardware / 5870 and 5850 Magical Clock speeds on: February 11, 2012, 05:28:07 PM
A long time ago I saw a super nice graph plotting hashrate vs memory speed. I cant find it anymore, so I made my own. I made a little script to run cgminer with various core and memory settings and let it run until it had found 100 shares.

This is the result so far (ignore the right Y axis, left one is correct):

On hindsight 100 shares wasnt enough, but a few things are already clear;
- Differences are relatively mild. I havent been able to find ckolivas' 20 MH boost.
- its the ratio between gpu and memory clock that matters
- 300 and 150 are both lousy for a ~900-1000Mh 5870

Tested with:
- Linuxcoin (SDK 2.4)
- cgminer 2.2.1

17  Bitcoin / Pools / Deepbit hopping on: February 07, 2012, 04:21:14 PM
Recently there have been various 105-115+% PPS schemes propping up.
The most sensible explanation I could see was pool hopping large proportional pools like deepbit.

Deepbit delays its stats by an hour, but I didnt think that would be enough to prevent pool hopping, since deepbit is so large, you might assume every new block that is found, is found by deepbit, and you'd be right 1 times out of 3. Good enough to extract a profit from the non hopping proportional miners.

So, I decided to have a look at deepbit stats, to see if I could find evidence of this theory. I collected the stats for last 5 days and plotted the estimated hashrate against block duration. And sure enough, there is a nice correlation:

edit: this graph is incorrect, see below.

X axis shows minutes it took to find the block, Y axis is estimated hashrate (shares / minutes).
Average is 24.7 minutes.

I discarted sub 2 minute blocks, but even so data for the shortest blocks are not to be trusted, since deepbit only gives a granularity of 1 minute. Moreover, I do not know how the lenght is rounded, so if 1m59s becomes 1 or 2 minutes. This could also skew the graph, but I dont think enough explain the correlation.

Deepbit rounds 1m59 seconds to 1 minute in the stats, so on average I would have to add 30 seconds to each block. Then we get this graph

X axis shows the minutes it took deepbit to mine the block (average is ~25).
Y axis show estimated speed (shares / time).

Correlation is much less strong, but its still there. Looks like almost 10% hoppers.

Tycho, can you shed some light on this? Or if you can, provide data thats more accurate than 1 minute?
18  Economy / Currency exchange / [fullfilled] 15 BTC for paypall on: February 05, 2012, 07:30:45 PM
I quickly need some paypal dollars/euro's and want to sell 15BTC. Only reputable buyers pls. PM me your offer.
19  Economy / Economics / Clarke and Dawe - Quantitative Easing on: February 03, 2012, 11:52:08 PM

and another quite brilliant one on European Debt Crisis :
20  Other / CPU/GPU Bitcoin mining hardware / Bitcoin Contraption of the week on: February 02, 2012, 08:59:50 PM
So what do you do when a 5870 fan fails, when the card is still under warranty, when there are warranty seals on the screws and you havent gotten an RMA number yet?

Simple, take a fan, a hot glue gun and fix it!

Except, one fan didnt do it. The original broken fan is still in there, and its not moving and blocking the airflow. So it overheated. Badly.

So you take a second fan. Better but still not good enough.

So you do the obvious thing and find whatever fans you have of roughly the right size and you end up with this beauty:

Now its back to 60C Cheesy.
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