B looks like it would get rained on. I assume Madrid does get some rain, at some point in the year..

Yes it would work. As was pointed out a few replies up, you need to match the novec product with the temps you want to aim for.

It is evaporating. If you did it in an open container, it would all eventually boil away: just like if you boiled a pot of water on a stove for long enough. The idea here is that you operate it in a closed or semi-closed environment, where the evaporated gas vapor is then condensed on some cool object (a heat exchanger or heat sink of some type). The condensed liquid will then drip down back into the bulk of the liquid around the hardware being cooled and this process repeats indefinitely. It's actually the same thing that is happening inside every fridge/freezer and air conditioner, except this time we're cooling something that's inside the cooling loop itself.

I suspect that smracer has a good deal of capital to throw at this project. And I suspect he's partly doing it for fun too. The reason I say this is that these liquids are extremely expensive ($250-350 per litre usually) and results in a relatively complicated system compared to using normal heatsinks and fans. Usually the only reason to do phase change submersion cooling on a large/commercial scale is to obtain obscenely high hardware densities, where space is of #1 importance. For example, this case:  http://hongwrong.com/hong-kong-bitcoin/

If you are getting sick cards, then most of the time it's simply too high memory clock or core clock, or cards running too hot.

Hook card up to a monitor, and run OCCT GPU stress test with error checking mode. Or you could use furmark which has similar features.

Run the card at the clocks you intend to mine at, using the most brutal shader/ram settings in those programs you can. This will reveal if the card is stable at the card's "maximum utilization" aka maximum power and heat that any miner algo could possibly throw at it.

Be sure to let the card temperature ramp up and equilibrate for some time, before judging if it's stable. If it's not, improve fanspeed and/or lower clocks.

Also something to keep in mind, with the new algos that use very little power, is on many cards you can undervolt the cards quite considerably. Because efficiency/clock speed is a non-linear relationship, you can find that for example a decrease in voltage of 10% will give a much greater than 10% improvement in efficiency. For some R9 270 cards for example, a 10% reduction in voltage will give about a 30% improvement in efficiency. This improvement is so dramatic because most of the R9 series is clocked at the factory right up to its stability limit anyway. tl;dr - unless you have free power its better to improve efficiency rather than striving for top-notch clock frequencies.

Yep I've mined about 100 BTC at least from CPU/GPU days. Of course, I do not have them today, I had power bills to pay and at that time mining to me was just something to keep my computers busy while they were running other stuff, I dont think many early miners had the foresight or true-believer-yness that bitcoin would become "something big".

My systems used to run computation tasks (BOINC projects) specifically the GPU accelerated ones. At that time I had 4x 4870x2 cards donating to those projects, and a few other random cards, meanwhile other people were solo mining BTC (which I had not heard about yet). Makes me very sad to look back and see my wallets these days, and mining maybe 0.01 BTC/day at most... soon to be 0 BTC/day.

There is no limit.

However, mining rewards will drop, as difficulty goes up.

Block Reward = 999/Difficulty^2

Note that -d is not the same as -D they are case sensitive.

-D refers to a device string, where you have platform and device. For 99% of computers, platform 0 is the opencl platform we want.

so try:

oclvanitygen.exe -D 0:0

and/or

oclvanitygen.exe -D 0:1

Otherwise, if you really want to use -d, then it should be -d 0 or -d 1, however, this does not work for a lot of people, hence why i suggest electing a platform using -D.

Monero: CPU coins are a risk, because eventually they are discovered by botnet operators, and as they begin to take the lions share of mined coins, the network can suffer as a whole and prices can crash. This can also stifle the adoption of the coin. It's happened to countless "CPU" coins already.

(I've considered Monero a CPU coin, because of the 1:1 CPU:GPU performance ratio, and there are much more CPU in the world waiting to be exploited than GPU, and, exploiting CPU is easier, because they dont have the complexities of different card configurations as is the case for GPU.)

As the difficulty has risen 300% or more in the last 30 days, it is possible this is already happening. Of course, it is impossible to prove. But in any case I will be steering clear of this one in terms of both mining and investing/trading.

Doge is an altcoin to bitcoin, so its price is expressed against bitcoin as price pair, like all altcoins are: DOGE/BTC or BTC/DOGE. If bitcoin price goes up, dogecoin price should go down. It's simple maths. The overal value of "a doge" remains the same at that instantaneous point in time, excluding other influences on prices.

In my oppinion this coin will continue to plummet for some time, but eventually, it will reach a new price and stay there. Doge has always suffered from oversupply and a lack of real uses for the coin. Example: Most people exchange fiat to BTC and then BTC to doge. Alternatively, most people mine doge and convert it straight to BTC, and cash out to pay their power bills or to buy more/new hardware. Another example: How many shops and websites accept doge compared to bitcoin? Given the recent price drop of DOGE, if you ran a website, would you prefer to be paid in DOGE or BTC? Remember that for most businesses making money is the goal, community issues are irrelevant; all that matters is profits at the end of the day for 99% of companies.

The community is "strong" but also comprises a larger % than usual of users who (no offence) don't really know - and often don't really care - about what they are doing. This is brings a lot of good and bad attributes to this coin, which could be discussed for hours. A more important point is that the dev team is relatively large and active, and have been for some time. For most altcoins you can't say the same, even litecoin is coming under criticism in this regard.

Another thing to keep in mind with dogecoin, is there are now 86 billion dogecoins in circulation. We are at block 290793, there is another halvening at 300000. Unlike some other alts and bitcoin, dogecoin production will slow to about 5.2 billion coins produced per year (going on forever) which is about 14 million per day. Currently miners are producing about 180 million coins per day. So, within the next two years, the number of doge entering circulation will drop by more than an order of magnitude.

All of these things contribute to the price now or in the future. With the issues and developments with bitcoin over the last 12 months I think dogecoin will be even more of a wild ride. With very large scrypt ASIC coming into sight on the horizon soon, who can say for sure how all these factors will influence the price going forward...

-Program could randomize port usage. (uTorrent is a good common example and has done this for years).
-That whole UPnP thing.
-TOR / VPN / Proxy.


tl;dr - No. _{Well, yes, but only if you decide to be a helpless victim if they try.}

Seems to vary a lot with driver version, my 280x only getting about 2.1 MH/s with pretty much identical settings. I'm on 13.12 still, not sure I can be bothered to play uninstall/reinstall/reconfigure-all-the-displays games right now though..

Hope you will add a control loop to turn off the power if the cooling loop fails or reaches some critical temperature. Imagine several thousands of dollars of fluorocarbons evaporating. 

Wow. Using bitcoinwisdom calculator.. even with low estimate of difficulty increasing (10% per jump) and my $0.27/kWH (heavily discounted) domestic power rate, there is no way I'd even make back half of the investment cost buying one of these. I guess we'll leave it up to those with dirt cheap / free power.

It will take far too long. Just try one part of the name instead.

Or set shaders to 0 and use TC by itself. Or also leave TC=0 and use rawintensity which is a lot like TC.

For scrypt-n, TC is usually half (or less) of what is known to be best for your cards on normal scrypt. There are heaps of sites that list these for most cards.

You just destroyed my brain trying to work out why it was only mining on one card.

It turns out that "devices" command line must now be specified in the pools section. Is there a list somewhere of command line options that you moved to the pools section of the config?

---

To those finding that marucoin-mod is slower than x13mod, try changing

"gpu-threads" : "1",     (set between 1 to 4)

and

"hamsi-expand-big" : "1",    (set to 1 or 4, check .bin file reflects this change)

Going from sph-sgminer to sgminer v5, I had to add "hamsi-expand-big" and change threads from 4 to 1. Now they hash at virtually the same. (Marucoin hashrate is truely terrible when threads is on 4).

Nice, what will be the immersion fluid? Be sure to put something like copper sulfate in the glycol loops to prevent inferior organisms taking over.

Different algorithms result in different GPU utilization. Utilization != % Load

Those of us who were around when bitcoin was mined on GPU, already know that different algorithms have different card utilization. SHA-256 always used less power than scrypt, which is relatively memory-intensive. More power consumed, more heat, more noise, etc.

X11/X13 coins take it to the other extreme, and result in very low GPU utilization (approx half of the normal power consumption of the card).

I have 9 GPU on X13 getting about 15 MH/s for 600 watts.

Not sure if anyone can help, I am having an annoying problem.

I have one profile setup for mining X13 algo coins and it works perfectly.

I have copied this folder and made minor changes to X11 algo, and added a new profile in CGWatcher. However... sgminer is closed immediately after it announces its API startup message. CGWatcher status says "refreshing devices".

I dont understand why it would work fine for x13 but not x11, there are no differences in config I can see...

If I launch sgminer by itself it runs just fine, so it doesnt seem to be a miner problem. The API address/port are the same for both miners.

Evaporative cooling is cost effective if you're in really dry climate. Or else you have a choice to pay quite a lot more to cool everything with refrigerated cooling ("AC"). You'd need to install a huge capacity system for that many miners.

The other option is to actively ventilate the rooms with very high flow of air from outside. You can calculate how much airflow (or air exchanges) will be needed if you know the heat output of all your miners, the heat capacity of air (google) and your typical outside temperatures.