A CPU has much smaller toggle rate [will use much less power than the Hashing chip ... maybe even 10 time less]. Getting 1GH on 130nm is probably also not easy.
Okay, I read some notes on this here and it makes sense. Basically, [for people reading about this too], the toggle rate is the number of transistors changing state per clock cycle designated a. The net toggle rate n is such that n = f × twhere f is the clock frequency and t is the ratio of transistors switching state per clock cycle. For a SHA256 ASIC, we would assume this to be 98% or 0.98, whereas for a typical CPU or GPU this would be much less as SHA256 hashing would not require state changes for transistors in components not used, such as the FPU. The total power consumption p of the ASIC is then p = n × transistor dissipation factor (constant for the same process, e.g. 130 nm, but becomes a smaller constant as the fabrication shrinks) because electricity is wasted (dissipated) with every state transition for the transistor. Thus, as tytus stated, this chip hashing at full speed would likely require some 2x-10x more power, making the TDP 120-600w. However, if the process were 28-45nm, a TDP close to that quoted by BFL may be possible, but it seems unlikely they have access to such an advanced fabrication method (which would require tens of millions of dollars in investment to get off the ground, most likely). See also: http://cis.poly.edu/cs2214rvs/powers03.htmSo, the power claims by BFL are actually dubious... which is not surprising, given the 6x difference in power for their BFL single unit between quoted and actual. This is all pretty suspicious. If BFL really wanted to keep the user informed, they could at least give the process they're working on, the transistor count, fab location, etc like a real company that does chip fab, but so far all they're giving us is a place to send money to them and a hashing speed. Further, BFL may risk patent infringement if they use published technical methods for the ASIC circuit designs. But since BFL has said mostly nothing about the way it works, who knows? edit: 10 BTC says they're just reselling CAST's ASICs for SHA256ASIC Technology
max f (MHz) Logic Area (um2) Number of eq. gates
UMC 0.18 μm 280 250,040 20.5 K
TSMC 0.09 μm 500 50,800 18.0 K So there you go, it's probably on TSMC 90 nm. If this is the case then the 2.5 W of draw for the jalapeno is probably not true at all. |
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A bug exists for scrypt mining algorithm in which thread concurrencies of above 8192 (required to get better performance on 79xx cards) fail, preventing the GPU from using most of its memory. This results in a -25% performance hit for 79xx cards mining the scrypt algorithm.
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why? can I somehow sell them for btc and come out ahead of simply mining btc?
They're about neck and neck right now in terms of profitability per watt, however, the profitability of BTC for video cards will be expected to drop upon the introduction of ASIC miners. ASIC miners do not exist for litecoin's algorithm (which is designed to be more ASIC resistant than SHA256), so GPU mining LTC should remain profitable for some time. Unlike SHA256, scrypt requires 8kb of L1 cache per process unit and as large as possible, as fast as possible RAM to store a constantly accessed buffer into. Hence, when ASICs are created for litecoin the gain in speed/watt may not even be on the order of a magnitude, whereas the gain in speed/watt in hashing SHA256 is about 100x (or two orders of magnitude). |
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Crazy, now running 5870,5850,5852,5830 off the single rail 850W...
Great tips guys, thanks.
Yup. The only OCZ psus to get for mining are the Z-series PSUs, which are up there with seasonic/corsair in terms of reliability (I own a 1KW and an 850W). |
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I put 18, the kh went up to around 400, but I had Q:38 A:8
if you go above 12, its will just be stalen  you have to tweak it pretty much, i got ~700 kh/s out of my bro's 7970 with -I 12, but with som good tweaks Share the tweaks, for the good of the cryptocurrency of course. Reaper config: host ltcmine.ru
port 8344
user xxx
pass xxx
protocol litecoin
worksize 256
vectors 1
aggression 20
threads_per_gpu 1
sharethreads 32
lookup_gap 2
gpu_thread_concurrency 24576 Should be able to get 700+ kh/s. I have a 7950 running this right now and I'm getting 550 kh/s. |
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Looking to sell (USD PayPal or Bitcoin) my 5870 ATI cards of which I have two available. I am looking for either an amount exchange or a quasi trade including a 5850 card (I need up to 3 of these). Anyone interested or looking for a 5870? I have little feedback here, but plenty on eBay, gametz, PayPal, Neogaf.
I would buy a 5870 for $160 shipped to Canada... They're EOL and 5970s are ~160 USD, so... Can pay BTC or LTC or Paypal. PM me if interested and I'll let you know where you'd be shipping to. 5970s are ~160 USD. Where please. So that I can buy them all up. lol. my mistake, put 160 in twice. |
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I'm not an electrical engineer, so probably someone who is will shit all over this. Anyway. I think these chips are small and probably on 90-130 nm technology. SHA256 hashing requires about 13,500 logic gates per circuit or 27,000 transistors. An AMD K8 130 nm CPU has about 106M transistors in 100mm^2 with a TDP of 60W, so we could fit about 3926 SHA256 hashing circuits on one of these ASIC dies. These hashing units run at 65 cycles per hash; we would expect from an immature 130 nm process for the ASIC that clock rates of 1 GHz would be achievable. This would mean 14.5 MH/s per hashing circuit or 56.9 GH/s per 100mm^2 die with a 60W power consumption. How does that compare to what has been given to us by BFL? The BFL single, which is assumed to be a single die, is rated at 40GH/s. With the above ignoring crucial things like transistors for I/O, it does indeed seem possible that the BFL single can provide 40GH/s at 60W on a 130 nm process. |
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Looking to sell (USD PayPal or Bitcoin) my 5870 ATI cards of which I have two available. I am looking for either an amount exchange or a quasi trade including a 5850 card (I need up to 3 of these). Anyone interested or looking for a 5870? I have little feedback here, but plenty on eBay, gametz, PayPal, Neogaf.
I would buy a 5870 for $160 shipped to Canada... They're EOL and 5970s are ~300 USD, so... Can pay BTC or LTC or Paypal. PM me if interested and I'll let you know where you'd be shipping to. |
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You can get a new 7770 for $90 AR (higher efficiency), so there's little incentive to buy a 5770 for $80. I think $50 shipped is reasonable.
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Don't use reaper, it's much less stable than cgminer and slower on the 7xxx series to boot. Use the following cgminer settings: --scrypt -g 1 --shaders 1280 --thread-concurrency 16000 --worksize 256 -I 13 for the 7xxx series you should use -g 1 and --thread-concurrency of (12.5 * number of SPUs) Intensities of 7-15 tend to work best, setting intensity too high gives horrible hash rates and all stales Should be faster than reaper if not as fast. With a 6870 you should be getting 360kh/s in cgminer (I get 180kh/s in cgminer easy with a 7770, which has half as many compute units). Additionally cgminer seems to use less power. |
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Ok finally solved. My issue with MSI AB showing blank sliders is apparently in newer versions of AB they dont include the Atipdlxx.dll, or at least if you copy Atipdlxx.dll into the MSI AB program folder from an older version of the driver (I used 12.1 whql version) then restart AB with the unofficial overclock mode2 option it shows the sliders again. With AB 2.2.3, amd 12.6 whql and the Atipdlxx.dll in the AB folder i can drag the slider down and set memory clocks to below core -150 Got the dll file from here : http://www.mediafire.com/?phl44hvned2pwab - just pasted it into the AB 2.2.3 folder. Will post an update with power measurements. kind regards here is the 12.4 dll if anyone needs it, took me forever to find it http://www.multiupload.nl/0BWAFN4UGM |
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They are steam keys from GPU purchases. I will refund you if they don't work.
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Current inventory:
Sleeping Dogs: 1.4 BTC
These are steam keys for NA
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LTC hash rate skyrockets, LTC goes up in value massively But do the two really coincide? I mean, wouldn't the mass influx of miners only serve to increase the supply? What will happen to the demand, then? Supply doesn't change, LTC output remains constant (more or less) due to the rapid difficulty change algorithm. However, if there are more independent, small miners moving from BTC to LTC who have already paid for their rigs in full or part from mining BTC, they will be more likely to hoard their LTC than people who have immediately invested large amounts of money into the technology (ASIC miners for BTC). It's clear with these digital currencies that as soon as you get a rise in value sparked, it tends to snowball until reaching a peak because when the value rises people tend to hoard instead of sell. I think this will be the case again with LTC. I would hope that coblee takes steps to modify the algorithm to make it more ASIC-unfriendly over time as I specified in LIP0001; I think as long as LTC stays GPU mined predominately it will rise as the "people's coin" that anyone who can afford a computer can get into, whereas bitcoin is very quickly going to move to specialized hardware, large mining companies, and profitability closer to 3-5% per year amortized like other commodity assets eg gold. The tradeoff is probably that LTC will always be a magnitude more volatile than BTC in the near future. |
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I think it'll go something like this Mass dumps of BTC because everyone wants to earn as high a ROI as possible and ASIC miners are useless for anything other than SHA256 hashing. Falling BTC price will facilitate more mass dumping. People GPU mining all move to LTC because BTC hash rate is too high. LTC hash rate skyrockets, LTC goes up in value massively. Right now I hold 50% BTC and 50% LTC. It's clear that the value of LTC is stable, as people (like me) are constantly dumping BTC mined into buying more LTC. I think it will follow the same path as Namecoin after merged mining
Hash rate skyrockets -> people with coin of little use -> dump it like ugly prom date All merged mine coins will fall into this trap because people acquire them for no extra cost and so just dump them. LTC will never be able to be merge mined with BTC, so it doesn't have that problem. |
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...nobody for or against? I personally see a ton of people moving to LTC after the release of ASIC mining for BTC, and I think the chain should be fortified against ASIC release in the long run.
Personally, I also think we should multiply by 4 or 5 instead of 2, as LTC is scheduled to halve block reward in four years, during which we can expect RAM capacity of video cards to more than quadruple.
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LIP0001 (Litecoin Improvement Protocol): At blockreward halving scrypt memory parameters will double
Theorem 2. The function SMixr(B, N) can be computed in 4Nr applications of the Salsa20/8 core using 1024Nr + O(r) bits of storage.
Users of scrypt can tune the parameters N, r, and p according to the amount
of memory and computing power available, the latency-bandwidth product of the
memory subsystem, and the amount of parallelism desired; at the current time,
taking r = 8 and p = 1 appears to yield good results, but as memory latency
and CPU parallelism increase it is likely that the optimum values for both r and
p will increase. Note also that since the computations of SMix are independent, a
large value of p can be used to increase the computational cost of scrypt without
increasing the memory usage; so we can expect scrypt to remain useful even if the
growth rates of CPU power and memory capacity diverge. http://www.tarsnap.com/scrypt/scrypt.pdfShort version: scrypt hash memory requirement = O(log2(N) * p * r * 128) Holding N (=1024) and p (=1) constant, scrypt hash memory requirement = O(r) So, if the parameter r doubles, the memory requirement should also double. Therefore, with LIP0001, at blockreward halving r = 2 * r and the memory requirement is doubled. The main purpose of using scrypt in litecoin was to prevent initially GPUs from mining the chain and now it is well held to prevent ASICs from mining the chain. By increasing memory requirements at every blockreward halving it should maintain memory hardness and ASIC resistance. See also: https://github.com/litecoin-project/litecoin/wiki/Scrypt-proof-of-workhttps://bitcointalk.org/index.php?topic=98535.0https://bitcointalk.org/index.php?topic=45849.0https://bitcointalk.org/index.php?topic=64239.0Edit: N should be the parameter changed, fixed. Edit 2: No, it looks like r is okay. I'd like some input from others on this proposition, though. Bubble boy claims: "log2(N)*p*r*128", so r should be okay.
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Bump
How much btc for 2x 5970 to sk?
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