Bitcoin Forum
March 19, 2024, 08:45:39 AM *
News: Latest Bitcoin Core release: 26.0 [Torrent]
 
  Home Help Search Login Register More  
  Show Posts
Pages: « 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 [29] 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 »
561  Bitcoin / Mining support / Re: orange sparks where psu connects to motherboard on: March 21, 2014, 05:26:01 AM
The 24 Pin connector only has 2 12 Volt wires. You are not supposed to install that many power hungry cards in one board.

Quote from: Wikipedia
The Molex Mini-Fit Jr. has a power rating of 600 volt, 13 ampere maximum per pin[11]
562  Economy / Service Discussion / Re: FINALLY! A simple bitcoin wallet for iOS, that works. I got the Pheeva! on: March 21, 2014, 03:45:46 AM

2. Verify your email / password


Very phishy.
563  Bitcoin / Mining support / Re: orange sparks where psu connects to motherboard on: March 20, 2014, 05:53:51 AM
With posts about hot cables, I am wondering about cracks in the insulation due to excess power draw.

Do you have more than 3 video cards mounted on the board by any chance (without powered risers)?

My hardware: 4 x sapphire 7950's- two on the mobo, and two with unpowered risers (I suppose this could have overloaded the mobo). psu is a Corsair AX1200i, and the mobo is an MSI 990-FXA GD65.

I would suggest either pulling two cards or using powered risers. You should replace the 24pin connector as well (which likely means replacing the whole power supply).
564  Other / Archival / Re: Pictures of your mining rigs! on: March 20, 2014, 05:35:03 AM
Love the modified server PSU, I've considered using them, but concerned over a potential increase in fire hazard. I know those dells have pre-configured kits, but didn't know if it can cause potential issues as I read a couple people saying they had hot wires to the touch.

If wires are hot, they are probably not thick enough. Hmm, third hit says 18Gauge is good for 16 amps.. would not want to run more than 5 though that. This pages seems to agree, but qualifies that with a maximum length.
565  Bitcoin / Mining / Re: Mining Safety on: March 20, 2014, 05:09:04 AM
phillipsjk, you pretty much summed up what I said from what I can see. The passive PFC supply will loose efficiency when the line voltage is dirty, since it does not have the extra switching circuitry. From my understanding, the point of the APFC was a boost converter between the input capacitors and rectifier. Because of the input capacitors and the boost converter, the "first-stage" switching supply appears totally resistive, or nearly perfect power factor. To do so, it needs to have a pretty close eye on the input voltage and waveform, so since it's always adjusting, trying to match, it ought to be more efficient adjusting right along with "dirty" input voltage, right?

I think my main objection was your claim that most power supplies (with automatic voltage switching) use APFC.

When I bought my "green" power supply (80%+ efficiency rating), I assumed, without checking, that it had APFC. My Watt-meter tells me it uses passive Power factor correction. (And the label does not make any PFC claims.) The PSU out of my old dell Optiplex has very good power factor: They may have used APFC to remove inductors to save space.

As I said, bad power factor does not directly effect the efficiency of the device. You draw the same wattage with good and bad power factor. The difficulty is that bad power factor requires more current to transmit the same amount of power (sometimes called "apparent power"). If the power  rating is measured in VA (Volt-Amps), that is an "apparent power" rating. Real power is measured in Watts.

With a resistive load, those will be the same. Power factor is a measure of how different those two numbers are. BTW, the Wikipedia article helped my understanding too. That is where I learned all those PSUs with crappy 0.67 power factor actually do have (passive (in the form of inductors)) Power factor correction. I know my vacuum cleaner has (probably passive in the form of a capacitor) power factor correction. Power factor is more important for large loads like vacuums or mining farms.

So if I can the the Ohm with a multimeter then I can figure out Amps with I=U/R, correct?  Have not seen or thought about that formula since college...

Simple multimeters don't work well on non-linear components like semiconductors, capacitors, and inductors.

Typically what is done to measure current (in the range of milliamps-amps) is to insert a 0.1 Ohm sensing resistor (keeping in mind that at 10 amps, that would drop 1V). For higher currents, you may want to look into clamp current meters or simply measuring the temperature rise to monitor power usage. Edit: my watt-meter just measures at the wall.
566  Bitcoin / Mining support / Re: orange sparks where psu connects to motherboard on: March 19, 2014, 07:12:53 PM
I would expect a burned-out component on the motherboard.

I would expect poor contact to cause blue sparks.

Of course, if orange implies fire, I would expect smoke as well.
567  Bitcoin / Mining / Re: Nearly burned down my home due to mining farm (tips on how to stay safe ) on: March 19, 2014, 05:37:36 PM
I wonder how many fall under UL approval?

Approval involves paperwork and probably testing

The only reason I know you can't get one-off devices CSA approved is I looked into the certification requirements once. I appears I was mistaken though: There is a "model certification" option. I tried looking up the file number of some old equipment and did not get results: even though the UL number still works (will have to investigate further).

In general, hobby electronics projects will not have approval.  This means you have to take extra precautions to avoid causing a fire. This may include keeping it on fire-proof materials, and unplugging it when not in use. Obviously, miners are not very useful unplugged. Edit: another way to limit risk of fire (hinted at here): reduce power draw as much as possible. Less power, means less heat; implies less fire risk (with miners that means: no overclocking).

Edit: I also wonder if the OP's miner was mis-wired. Each wire pair from the PSU can safely carry about 5 Amps. That implies 6 wire pairs or 12 wires total going all the way back the the PSU. Splitters are a no-no (unless you are cutting off the common end).
568  Alternate cryptocurrencies / Altcoin Discussion / Re: Juba - The first cryptographic coin to promote peace in the Middle East! on: March 19, 2014, 05:10:55 PM
Stop hating on the OP. Juba was featured on CNN Cheesy

http://www.youtube.com/watch?v=ZXK2HRffa24

Can you please tell me ~what time?
I don't want to watch much of that crap.
Thanks

I think we got trolled. Skipped though it, and it appears all about killing American soldiers in Iraq.
569  Economy / Speculation / Re: my intuition says: we're sitting on a rocket about to be ignited on: March 19, 2014, 04:58:23 PM
fair enough. wasn't sure if philip was being sarcastic or not because of Poe's Law -- sounds exactly like something a newbie would actually believe Cheesy checking out philips post history and join date though it's obvious he is an oldfag like us Tongue

I was being serious, actually. The difficulty is that I probably won't be able to buy BTC for at least a month. By then, the market may have "corrected." I guess I should have used the future tense, but with no time-frame, that would be a tautology (there will always be missed buying opportunities).
570  Bitcoin / Mining / Re: Mining Safety on: March 19, 2014, 04:32:28 PM
A waste of money, nearly all ATX power supplies made use what's called active power factor correction. I believe this came from wikipedia...

Active Power Factor Correction does not directly reduce power consumption. Most old/cheap power supplies appear to use passive power factor correction. (They get a power factor of like .67 instead of 0.5). Where PFC reduces power usage is in transmission losses.

I have an 80+  Power supply that does not appear to use APFC. It is also auto-switching. In general, switch-mode power supplies are tolerant of power (voltage) sags (but will draw more current to get the same power). The reason is that they first convert the AC to high voltage DC, then use an inverter (at about 20kHz instead of 50/60 Hz) to get the low voltages.

571  Bitcoin / Mining / Re: Nearly burned down my home due to mining farm (tips on how to stay safe ) on: March 18, 2014, 05:12:41 PM

I would think they would deny coverage.  It's not like we are using the PSU's as they were designed to be used.  Here in Canada everything has to be CSA approved.  Not sure about anywhere else, but I would think all Countries have similar laws.  I highly doubt any of the equipment meets the safety standards required.


CSA only approves mass-produced devices. If it is no longer being produced, it is no longer CSA approved.

For that reason UL approval is also accepted.

That still means one-off jerry-rigs may not be covered if they cause a fire Tongue
572  Bitcoin / Pools / Re: [185 TH] p2pool: Decentralized, DoS-resistant, Hop-Proof pool on: March 18, 2014, 04:14:50 PM
I am in Canada. I am also using a commercial Internet plan so that it does not get cut off for "server hosting".

For some reason, 300GB is a number that keeps coming up as being abusive. That works out to less than 1Mbps (over a whole month).

Edit:
Quote from: ARCHIVED -  Telecom Decision CRTC 2010-255
45. The Bell companies' proposed economic (Internet traffic management practices) would include an excessive usage charge of $0.75 per additional GB of use in excess of 300 GB monthly for a (wholesale Residence Gateway Access Services) ISP's end-user if, and when, they introduce a corresponding charge of $1.00 per GB of use in excess of 300 GB monthly for their retail customers. Certain GAS ISPs submitted that the Bell companies' application of this wholesale charge would be anti-competitive and could be implemented with virtually no notice of the date of its imposition.

46.     The Commission considers that the application of the Bell companies' proposed excessive usage charge for GAS would constitute equivalent treatment of their GAS and retail Internet services if an excessive usage charge of $1.00 per GB of use in excess of 300 GB monthly is introduced for all their retail Internet service customers. The Commission considers, however, that the Bell companies should provide advance notice to GAS customers that this charge will be implemented.
- http://www.crtc.gc.ca/eng/archive/2010/2010-255.htm
573  Bitcoin / Pools / Re: [185 TH] p2pool: Decentralized, DoS-resistant, Hop-Proof pool on: March 18, 2014, 03:54:21 PM
Massive is relative. By your definition $1 would be "massively more" than $0.01 ("It's 100 times more!") but its still only a dollar.

As I said, if you are running a bitcoin node already, the added cost running a p2pool node is minimal. Certainly not everyone does have a bitcoin node.

Running a P2Pool node Increases my operating costs by about 10%.

In that post, I estimate that P2Pool makes the machine draw an extra 20Watts or so. That is 14.4kWh/month or about $1.44 assuming 10 cents/kWh.

It also appears that P2Pool uses about 6% of my 300GB bandwidth cap as well. That works out to about $6.60/month. (Bandwidth is expensive for some reason). (Calculation: 4.15GB/7days*30days/300GB*100%)
574  Bitcoin / Pools / Re: [185 TH] p2pool: Decentralized, DoS-resistant, Hop-Proof pool on: March 18, 2014, 07:29:07 AM
My ASIC is an ASICminer blade V2. The 22% haircut is barely tolerable (consider it a donation). Extending the share target to 30 seconds really helped though.

Quote
My machine is one of those ought's machines that supports 64bit processing, but only has 32 bits of address space. I suspect if pypy worked with no problems for you; your python modules were probably not c-optimized.

Which modules? I'm using whatever python module come from apt-get on ubnutu 13.10? (Pretty much the default install instructions for p2pool if I recall correctly.) Do you know if there is problem with those?


I posted the error messages in my earlier posts.
Quote
Twisted is known to work with PyPy. Some optional C optimizations must be disabled at build/install time. Twisted on PyPy runs faster for most benchmarks.
- https://bitbucket.org/pypy/compatibility/wiki/twisted

Since pypy did not detect the installed modules, they must have been using the C optimizations (Python detected them).

Quote
PyPy has alpha-level support for the CPython C API, however, as of 1.4.1 release this feature is not yet complete. Most libraries will require a bit of effort to work, but there are known success stories. Check out PyPy blog for updates.

C extensions need to be recompiled for PyPy in order to work. Depending on your build system, it might work out of the box or will be slightly harder.
- https://bitbucket.org/pypy/compatibility/wiki/c-api

The "problem" with pure python modules is that they are interpreted. This is slower than native machine code.
575  Alternate cryptocurrencies / Altcoin Discussion / Re: Juba - The first cryptographic coin to promote peace in the Middle East! on: March 18, 2014, 04:31:07 AM
you're all so vicious. good luck OP in your endeavors. interested to see what new ideas you can develop. thanks.

Thanks for the encouraging words. I am all cynical too.

I find it hard to believe they are going to be able to give way the entire pre-mine with an opt-in SMS service.
576  Bitcoin / Bitcoin Discussion / Re: POLL: How likely do you think it is that Dorian is Satoshi, founder of Bitcoin? on: March 18, 2014, 04:17:46 AM
I'd like to co-opt my own thread to ask a dumb question I can't find answered anywhere: On our profiles, what does "Activity" mean? Mine has been stuck at 28 for a good long while and I can't figure out what makes it budge. Does this mean I'll have "newbie" stamped on my forehead forever? Or is my newbie status a function of # of posts?

Post count is a factor, but scammers were gaming it. I don't post much, but I have triple-digit activity because I was here since 2011.

Thread explaining it.
577  Economy / Service Discussion / Re: I'm not receiving my bitcoins on: March 18, 2014, 03:51:13 AM
It is the the site.

These days Bitcoin faucets are essentially scams.

Quote
What's the MoneyBox?
You can delay your payments until you decide, and send them in a bulk. Due to anti-dust measures of the latest bitcoin revisions, minimum payout is 5500 satoshis.
- http://www.bitcoins4.me/faq.html

5500 satoshies is currently worth about $US 32.38 mills.

You may not be familiar with the unit of measurement. It is commonly used in property tax assessment (ie: the mill rate).
578  Bitcoin / Bitcoin Discussion / Re: Can you see the blockchain being used to register votes in general elections? on: March 17, 2014, 11:30:44 PM

Then apparently we're all fucked. Cause in the current system, votes get flipped, lost, changed, etc.  

I was kinda hoping that at our point in human civilization we have learned how to make voting work. Man I feel like humans are dumb animals who can blow shit up but not count worth a damn.

Canada uses the KISS system:
  • paper ballots/pencils
  • Sealed ballot boxes
  • Manual counting

We get the election results within about 6 hours, barring judicial recounts.

Granted, Canada uses a relatively simple First Past the Post voting system.

Quote
I guess let me ask a question. How anonymous is the current voting system. Don't the ballots have a bar code on them. Don't the polling admins known what day and approx what time you voted. They check my id when I arrive and hand me an "anonymous ballot". How about absentee, they mail you a ballot, no tracking there?

In Canada, the serial number is torn from the ballot before going into the ballot box. While it may be possible to figure out the order of votes, actually trying to do so is illegal. Because two people count the ballots, trying anything funny would get noticed.
579  Bitcoin / Mining speculation / Re: people buying used miners on: March 17, 2014, 11:22:45 PM
Yeah, it's crazy. I watched 38Gh/s miners go for $500+ on ebay. That's more than $12 per Gh. People buying like that are what's making the price go up. A Gh is not worth more than $3.

Praytell, where can I buy mining hardware for less than $3/Ghash?

Assume I don't want to budget more than $1000.

I would also comment that these devices on e-bay are "in hand", meaning they may ship in less than "two weeks".
580  Bitcoin / Pools / Re: [185 TH] p2pool: Decentralized, DoS-resistant, Hop-Proof pool on: March 17, 2014, 09:06:15 PM
Most of the ASIC problems you identified last year don't exist any more. This was mostly solved by the ASIC miners working better. As you correctly state, there hasn't been

You can see from my graph that it is not fixed for me. The fix was to extend the block-target to 30 seconds. With a 10 second block target, I would have >65% DOA shares on average because the round time on my ASIC is 12.8 seconds (and does not support longpolling). As it is, I expect at least 22% DOA. In practice, I am getting 30% or more.

Quote
How would this be different from the graph that is currently displayed?

A P2Pool getblock template lantency graph would tell me how long P2Pool spends processing it's own blocks. I suspect that it runs several seconds on my machine. I could artificially lower the bitcoind getblocktemplate time by:
  • Un-nice-ing  bitcoind. This will actually slow down P2Pool
  • Closing bitcoind to incoming connections as suggested. I want to contribute to the Bitcoin network as much as possible. Mining is just a bonus.
Edit: If I assume the P2Pool getblocktemplate processing always takes the same amount to time (thus makes a graph pointless), I can calculate it from my hash-rate graph. 30% DOA - 22% Expected DOA = 8% of 30 seconds of round time being CPU latency.
30secondsx8%=2.4 seconds - 0.7s  Bitcoind latency = 1.7 seconds P2Pool latency
--some of that may be due to limited network bandwidth too.
--My machine is dual-core as well, so that simple math may not hold.

Quote
Regarding my hardware it isn't that the system is so new (or fast), it is just that I had some extra 4 GB modules sitting around so I used them.

My machine is one of those ought's machines that supports 64bit processing, but only has 32 bits of address space. I suspect if pypy worked with no problems for you; your python modules were probably not c-optimized.

Pages: « 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 [29] 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 »
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!