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yeah i guess just gotta wait to get one :/
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ngzhang offers great customer support and Icarus boards have the highest resale value compared to X6500 because there are many available IO pins (80-100+), not to mention chip interconnection paths.
Also his design uses 100% solid state capacitors which is good for longevity.
* I'm not implying that X6500 is bad, just pointed some pros of Icarus.
Just an another example how chinese made stuff can be of amazing value  But yeah, one could use that board for something else too |
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At least that pizza looks VERY delicious!
I wish one could get anywhere near like that around here in visual deliciousness factor at the very least.
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Lol: http://www.avc.com/a_vc/2012/03/raspberry-pi.html"When the cost of tablet displays comes down, which they will, I think we'll see sub $100 tablets. And I suspect that will happen in the next 3-5 years." Well, i guess i dreamed up the 56$ tablet i got sitting on my living room table  It actually works quite well, has android on it. I played Angry Birds on it for a while and my dad used it for surfing |
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Indeed, wouldn't prob last that long, but it's nice to see that a "lowly ARM CPU" can pack even that much of a punch. Where did you find them? I've been wanting to order one but can't find anywhere for sale :/ |
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Wow indeed. These numbers a low, but thats not bad for what it is. Even the 4550 cards got about 7mhs or so. I doubt someone will buy 500 units to get a ghs though.
W/Mhash does not work with Raspberry Pi at all (3.5W) Any GPU is many times larger than Raspberry Pi, consumes atleast 10s of times more electricity. Not a comparison really. For something which is made to be as cheap as ever possible, and achieving speeds of a Atom ... That's quite significant. You are not going to line this up with latest Intel 8core extreme series, so why would you line this up with a GPU? |
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So i'm stuck with Icarus/X6500/Z-Tex as my FPGA options, from which Icarus looks to me by far superior.
Just out of curiosity, how do you come to that conclusion? What are the cons of X6500 and ztex? Mostly personal preference. That's why looks to me by far superior Actually i mean more like "so far", kind of language barrier going on there. Z-Tex tho is expensive per Mhash, far too expensive. X6500 is retailed by Cablesaurus and i dislike cablesaurus too much for their insane markups, but more the reason was package contents are not listed (no idea does it even include power adapter, and can i get it with euro plug) Icarus comes with best performance guarantee too, and dunno, i somehow like to buy stuff from china Some of chinese stuff is just awesome value, tho sometimes you get total garbage. In some things tho they price themselves out of the game, being greedy and all that stuff, but that usually happens only with outsourcing, the reason for outsourcing is lower cost, and they expect you to still pay almost same rate as a local guy without language barrier, high education and higher quality of work. Developers are paid 70-120$ a week generally in China but the outsourcing companies are asking for 1125$+ for junior developer a week. Local junior developer costs half of that (straight out of school or still at school) here at Finland. Tho, if that junior developer has even 1-2 years of work experience salary is easily doubled up at times. I'd really like to get few BFL Singles, but the customer service totally sucks, the insane shipping costs (basicly a markup, nothing else), and their intention to significantly raise prices (likely pricing themselves out of the game) makes me not to want to put significant effort in using BFL Singles. (Developing cluster cooling, automation if needed, racking/stacking, things which are specific to BFL Singles and not easy to adapt to other FPGA miners) Just something puts me seriously off about them, they feel arrogant. No other company has issues on shipping to non-PP registered shipping address neither, so that puts me off as well. Also the fact i have to likely wait 3months for delivery.... |
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There is nothing fancy about distilled water. It's basically just boiled water. It costs about 89 cents a gallon and any store. There is no point of putting it in a car since they heat the water enough to kill bacteria anyway. Clearly you have never even looked inside of a cpu block. Even the EK High flow block is a lot smaller then 5mm.
Water cooled mining rigs last longer, stay quiet and run cooler. My water cooled rigs pretty much never crash and it more then makes up for the extra time putting them together. Everything you have mentioned on this thread is backwards. We are not talking about water cooling 100w cpu blocks or race cars. A decent mining rig draws 800-1100 watts. Anyone with any sense is going to get a nice pump. You obviously don't have any interest in water cooling mining rigs or any experience doing it. I don't know why you are even acting like you know what you talking about, clearly you don't.
wow, i didn't know distilled water is just boiled! OMFG!! j/k I've even built my own water blocks. The commercial products i've seen mostly use 10-15mm hosing. Many of the water blocks has been very simple, hose in, hose out, just a big water space inside the block, and some had ribs to have bigger surface area. Good quality water pump is a must, i've never said you should skimp on water pump. Not once. Not even hinted. No matter how you put it, 800-1100watts is still a small heat load relatively, and one definitively shouldn't over complicate things. Keep It Simple, Stupid! or K.I.S.S. I can see the point in adding the silver coil, or even "dead water" or other chemical to kill bacteria, but i don't see a point in over complicating simple things. None of the commercial single system water cooling package i've had the displeasure to work with had nothing like this. One had so bad additive it kept on accumulating in corners and i had to spend significant amount of time running hot water through it to get that stuff out. Use copper blocks, use brass fittings if you go with standard hydraulics fittings (ie. NPT, BSP) hell maybe even AN-fittings (aluminium btw!) even tho that's total über overkill, or maybe just use basic hose barbs (1.5-3$ each) and clamps. Go with a high quality pump with a backup pump (2 parallel) so no need to monitor constantly. Use basic standard rubber hose, if you want to be cheap even garden hose will do the trick (yuck). Add a little bit of glycol for protection of the metals. and do *NOT* omit periodic maintenance (ie. once a year) tho adding dead water and silver coil costs next to nothing vs. the other gear. So why not add them. I must admit tho, i hate water cooling generally, makes maintenance a bitch in regular systems, but for servers (or bitcoin mining cluster) it makes tons of sense. You should take a look at how industrial water cooling systems work ... They are remarkably simple by design. Even those cooling tens of thousands of servers. I started fooling around with water cooling when Thunderbirds were a new thing (or maybe even earlier ...), didn't like it then for single systems, don't like it now. Tho a new corsair's set made it remarkably simple, infact so simple i might consider that for myself too, after i've seen how a system like that works later down the road (maintenance wise): http://www.corsair.com/cpu-cooling-kits/hydro-series-water-cooling-cpu-cooler/hydro-series-h100-extreme-performance-liquid-cpu-cooler.htmlJust installed H100 for a customer |
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Bitcoin is a 80 byte block.
4 bytes version
32 bytes previous hash
32 bytes transactions hash
4 bytes timestamp
4 bytes nounce
4 bytes difficulty
(last 3 times 4 bytes might be in different order, can't remember right now)
After padding the block is 128 bytes.
The first 64 bytes of the block is the same during a work unit so that part in only hashed once.
The second part of 64 bytes is hashed many times with each time a different nounce.
Each 32 bytes output is padded again to a 64 bytes block to be hashed again.
So the effective hashing rate would be around 1629.47k / 2 = 814.735k according to the OpenSSL test.
wow, that's not bad at all for something like raspberry. |
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yeah sounds a bit like electronics skills come in handy with FPGAs to keep them working, and AC not a bad idea. Was thinking of installing to my office 1kW AC unit, afaik those small ones too get upto 1:3 efficiency ... I could keep the FPGAs churning happily @ 17C ambient all summer through. GPUs not so much, but i got another location which is 900m3 of poorly insulated space to dissipate heat into ... Before even installing exhaust and intake duct fans. Problem is electricity costs here 0.19$/kWh, but on 2nd location it's billed only once a year so i can choose the best time to sell BTCs to cover that. Trouble is, i've had now 2 GPUs fail within a week... Even before using GPUs for BTC i've had several fail on me, so i'm starting to think the average lifetime expectancy might be quite a bit lower than generally thought for GPUs. FPGAs are OC'd to their very edge for mining purposes as well... Top that of that BFL wants over 80$ for shipping for each one .. Ridiculous - and even tho i have warehouse to have shipped to @ States, there is no method for me to use that address as Paypal doesn't accept foreign shipping addresses ... So i'm stuck with Icarus/X6500/Z-Tex as my FPGA options, from which Icarus looks to me by far superior. Tho, i can probably offset some of the acquirement cost by MFG'ng stackable casings for them with optimized cooling  But no way knowing before i have enough to properly test and design the casing. |
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Was just looking about this ASIC, i see it has been mentioned here, but this seems to be the only thread? Didn't anyone look in detail? Afterall, it's a function of costs, if these chips are low powered and cheap, why can't you chain them? Looking at these two: http://ipcores.com/sha_ip_core.htmhttp://www.cast-inc.com/ip-cores/encryption/sha-256/index.htmlI guess single chip achieves atleast 4.24Mhash/s? That's quite weak, but if a single chip costs less than 1.7$ and consumes less than 0.2W it could be viable vs. current FPGA solutions. Hell, even at at 1W per chip it would achieve a nice ratio. It has so few gates it can't consume much! |
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In other words the life expectancy is anything between 3months and 10years, and no one has nfi.
Thing is i'm trying to decide to invest between 7970s and FPGAs, and it all depends upon which i can expect to utilize longer ... The payoff period in any case is going to be a long one, thanks to high electricity prices (0.19$/kWh)
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Also the heat transfer rate sucks for computers which cannot exceed too much the ambient.
If you can have large difference on ambient oil works.
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After a crash on one of my 58xx cards due to a bit too high clock, now BAMT refuses to set clocks for the high usage profile. Infact, the high usage profile memclock got applied to idle :/
Had to disable the GPU because @ stock voltages it's running hot and slower than an undervolted card :/
Any ideas what's going on?
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I think GPU can happily mine for much more than 3 years if kept at a decent temperature.
GPUs can last way longer than that, but generally people would throw them away after 5 yrs. I've yet to have a GPU fail on me besides the fan, which is no big deal. Mining is a 24/7 task ... Does not relate what's the MTBF in the regular user usage and what is it in 24/7 100% utilization. |
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Yup, oil cooling totally sucks. It's just every power company in the world has no clue what they are doing. I bet you could become a billionaire by selling them water blocks.
For this task it does. Just because something works in another scenario does not mean it's a silver bullet for all scenarios. |
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Point was, and still is, you don't really need all that fancy stuff, when basics are more than sufficient for relatively small heat loads.
No need to over complicate a very simple thing. All those little stuff fast adds to quite a bit of extra expense, never mind requirement for extra planning.
Hell, a huge european DC uses basicly tap water as a total loss coolant for TENS OF THOUSANDS of servers. Works just fine, most stable servers i've had the pleasure to work with.
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So what about distilled water to keep this discussion in the spirit of the post? I know that its not a long term solution, but what are the pros and cons.
Fried system?  But i guess if you use enough of electronics varnish ..... |
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Oil is not a good cooling solution even with radiators.
If you RTFA you'd notice they are running at near cracking point - the temperature where CPU simply cracks internally due to heat!!
Oil sucks as a cooling medium in this usage. (Infact, in almost any)
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Mineral oil has quite poor thermal transfer capacity, google around about it and you'll notice it doesn't really work for computers at all.
If you see the load temperatures in that article it becomes imminently clear ...
Bubbles.... So basicly, they are moving the heat out with air
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