I've been considering the best way to determine a sweet spot for my avalon...  currently running at 343 (it just "feels" like a nice balance between hashrate and HW errors), but now I'm getting that overclocking itch once again.

I'm trying to devise a method that is slightly more scientific than my gut feel. Perhaps it could even be integrated into some kind of algorithm that could be added to the firmware to improve the auto speed setting? I don't know if that's even possible. Also I'm not really sure what a lot of the numbers mean in the web interface cgminer status tab, so I'm just guessing at a lot of this. Corrections to my assumptions/mistakes would be appreciated.

So, I'm just guessing at what all those numbers really mean, but here's what I'm thinking.

if:
HW = Hardware errors
Diff1Shares = equivalent number of shares if submitting at difficulty 1 (not sure whether to use this or DiffA ? )
MHSav = MH/s average

then:
EHR = Effective Hash Rate = MHSav - ( MHSav * ( HW / Diff1Shares ) )

So, what I'm gonna do is just keep increasing or decreasing my Frequency until I can find maximum EHR. Makes sense?

ckolivas 0703 firmware is highly recommended, my machine (batch 2) was soft-rebooting every few hours, tried 0703 and over 5 days running now. (I have not had an unexpected re-boot for almost 2 weeks now, but I have manually re-set after trying different hash speeds)

-just to add to what Jestre said, as far as I can understand it, the latency of the connection will have a much greater effect on your performance than your bandwidth. Bandwidth requirements are pretty much negligible, whereas poor latency could cause you to submit more stales... I think...

dude, he just bought the thing second-hand, so he's already paid the premium. Selling this on ebay would be the same as asking for a refund (and he would probably not get as much as he paid, but you never know)

At latest update he had earned 23.5 BTC in 2 days already, and that was almost a week ago! (admittedly a far cry from the roughly 500 BTC to justify a $50K price, but well on his way)

btw Brit, an update would be appreciated, if you're still watching this thread...

Huh?

Summer is the primary reason that GPU mining becomes pointless for most folks. In the winter, these things give off lovely, life-saving heat! Especially if you run electrical heating (not really sure who does that, we all heat with natural gas up here in Canada, but I've heard it's done in other places)

In any case, the electricity being converted *almost* directly into heat by GPU mining is a benefit in the winter. (even if it only reduces your gas bill by a small bit)

On the other hand, running these little furnaces in the summer becomes a detriment as it requires even more electricity in the form of air conditioning to maintain a liveable atmosphere.

Thanks razorfish! Those numbers from thegenisisblock are quite sobering, and hard to refute. That is the best mining calculator I have seen, and with all the new companies preparing to unleash more TH than we've ever seen, it seems that the current 62% per month increase might almost be conservative 

Right now, electricity costs are almost negligible because of the massive advantage over the old tech (GPU's) but when you look at the numbers, even ASICs will quickly (well, within a year or so) become money losers - not even counting the initial purchase price. Never mind what you paid for it, without a massive increase in the value of bitcoin, you will be bleeding out money just from turning these things on.

This data also vindicates the decisions of the brave souls who paid massive premiums for immediate delivery (well, within a week or so, normal shipping delay) -- Whether it be ASICminer "high prices" or buying a second-hand unit from a BFL or Avalon customer; the way the numbers are looking, the window of opportunity is closing fast!

Yes, those 8 pin connectors with the * beside them are all 6+2 connectors and can be used for 6 or 8 pin needs.
You should be able to power up to 6 devices that require pci-e power provided it doesn't exceed the rated 83 amps or 996 W draw on the 12V rail.

sorry, this is a little late and I'm sure you've already made your choice, but the comment about "I don't care about power $ or noise" prompted me to drop my 2 cents in here...

I just recently bought one of these seasonic 1000W platinum PSU's and I absolutely love it so far (will have to wait 7 years to see if it out-lives its warranty, lol)

For me, $ was also not an issue, and this is not a cheap PSU, so I'm sure there might be a better value for the dollar. But when considering the cost and availability of a power supply vs the kind of hardware we are powering, it does not make sense to me to skimp on a PSU... Also, heat and efficiency (they kind of go hand-in-hand) are a big deal for me, and this PSU is simply excellent in that regard.

I cannot recommend any other PSU as highly as this one. If anyone has an opinion of a better 1000W (or higher) PSU, please bring it to my attention. Thanks.

should allow for multiple choice, I find I get a higher hashrate and longer times between reset (avalon batch 2) when using load balancing between 2 or more pools. (currently using ozcoin and bitminter)

ok, makes sense to me, thanks.

Preamble: I am relatively certain that KNC Miner is not a scam. (about 75% certainty) I have serious doubts that they will meet their targets/estimates in terms of hashrate and delivery dates. (less that 50% certainty) but I am considering taking a risk on the new Mercury device... (pretty affordable entry level device, limits my risk to acceptable levels.)

Question: What do the little grey numbers below the various products mean? You can see them from the "Miners" tab on this page -> https://www.kncminer.com/categories/miners

Currently there is a 12 below the Mercury, a 34 below the Saturn and a 250 below Jupiter. Does this number mean anything? I assume it has *some* kind of meaning, or else why is it there?

If I were to assume I would guess that this number represents the number of orders, but I would appreciate some clarification on this before I throw 25+ bitcoin on this gamble.

Any educated guesses are welcome, but clarification from a KnC official would be preferred.

-Thank you.

Congratulations Brit! (not for having a mini-rig, but for having the guts to make a big decision and follow through)

I hear a lot of panic about the difficulty but the rate of increase has consistently been lower than my expectations for going on 5 months now. Back in February when I was considering ordering batch 2 Avalon or BFL, I was basing expectations on a network difficulty of 70 million by the time it was delivered... here we are in mid July and we are not even half that. (though 70 million might be pretty close to the difficulty by the time a BFL device ordered in Feb gets delivered)

And don't listen to anyone tell you it's a bad deal because X miner that does Y GH/s for Z dollars will be arriving "soon" -- That is all uncertain and unproven, and uncertainty means higher risk (and also higher rewards if everything goes smooth)

You paid a very high premium for certainty, which lowers the risk, and reward. 

I'm not going to wade through the whole thread because "I've been down that road, I know exactly where it leads..."

but I feel this statement from dwdoc hits the nail on the head.

What did they say in the article? 35 employees I believe? spread between the normal operating overhead of the company I would guess there are less than 20 people actually assembling these devices?

One could imagine how they would have a rough time trying to fill their backlog.

Much easier to simply order the chips from a facility that is actually capable of mass-production and then re-sell the chips to industrious and motivated third-parties who are willing and able to do all the hard work.

things may change fast in the tech industry, but the difficulty, or total hashrate, is rising even faster.

the advantage of being first to market in bitcoin ASICs is enormous and has been proven by Avalon and ASIC miner. personally, I feel that chasing the smallest process size possible should take a back seat to getting a working product done... IT WILL NOT MATTER if your design is slightly, or even greatly, more efficient if you are late to the party.

(*personal case in point: after missing out (or rather, opting out) after seeing the clusterfuck that happened on the Feb 2 release of batch 2 Avalons, I made a purchase of some BFL devices. that was around Feb 10. About a week later batch 2 round 2 from Avalon was released and I got in on that one. I thought it would be a close race to see which device I received first, I preferred the BFL design because it was a smaller process size and a flip-chip design.

My Avalon has almost broken even in the 3.5 weeks I've had it running and my BFL order I likely won't see until some time in September if I'm lucky.

The point I'm trying to make is that you need to choose between using a more advanced technology that may take more time to get to market, and using more commonly available tech that you can produce right away. So far, the latter approach is winning hands down.

I'm sorry to hear that about the height of the chips. I would prefer a design that would allow any standard CPU heatsink to be used. Very interested to see the results of the shim/heatspreader idea... I expect it will be less than optimal but I'd recommend that you make this option available as it would make mounting a water block much easier for those who would like to go that route...

Have you considered a custom designed attachment kit? Perhaps something like a back-plate with a few simple bar springs to apply pressure? I'm thinking that a thermal pad interface is going to be necissary but it would be awesome if you could figure out a way to have a more direct connection using thermal paste...

If you do indeed find that a custom heatsink is necissary, please go with a copper base plate with heatpipes transferring the heat to a large aluminum radiator with fan. pretty much the standard premium heatsink design and in my experience it is extremely effective.

Thanks again for all your hard work, this is a very exciting project and I will be watching with great anticipation.

Did you set a static address on your laptop?

May or may not need a crossover cable,

google "How to set static IP"

I mean the 6 pin modular connector, the HDD was a 2.5" with sata power connector. I used an extra connector from one of my other modular PSU because the 850W enermax did not come with any extra connectors for the 6 pin connections.

How did you power fans and HDD and stuff? did you use a connector from another PSU like I tried?

NOTE  Re: Enermax 850W PSU that comes with some avalon batch 2.

I upgraded to a larger PSU while trying to troubleshoot some problems, it did not seem to be the problem, but I left the larger PSU in the avalon and thought I could use the 850W Enermax to power a small 2X7970 system... connect the 24 pin to the MB, connect one of each 7970 to the PCIe plugs, good to go, right?

It powered up just fine, but got no OS loaded error... doh! forgot to plug in the HDD... no big.

so then I pluged in the HDD to one of the 6 pin connectors on the PSU, no boot, no power on, no nothing... I tried a couple other of the 6 pin connectors, first one, same thing, second one, the system would power up, but I still get no OS error... boot into bios, no HDD detected... weird.

So then I thought I'd try another HDD, maybe that one died in the 1 week that it's been disconnected?

Bad move.

Sparks and then FLAMES started shooting out of the HDD. I kinda freaked/zoned out so it took me a few seconds to pull the plug.

Has anyone else tried to use the Enermax 850W with the chinese writing for a normal computer? Is it possible these PSUs are wired differently? I thought it was a standard ATX? maybe I just had 2 bad HDD in a row? (not willing to risk a third) How long 'till my apartment no longer smells like blue smoke?

ADVANCED OVERCLOCKING TECHNIQUES

After typing out the above - relatively safe - method, I thought we might explore some best practices for finding the true optimum speed of your individual Avalon.

As I understand it, the -auto option will simply increase clockspeed slowly until an arbitrary number of HW errors are produced. This is a quick and easy way of doing things and very useful, but it's not perfect...

Overclocking hardware for long periods of time is all about balance. Anyone familiar with regular CPU overclocking will know that you will normally hit a wall where increasing voltage will begin to experience diminishing return with respect to clock speed. This wall is usually parabolic and once you approach this level you will require excessive amounts of voltage and cooling to go any further. This may be acceptable when trying to reach a world record on a "suicide run" but it will not cut it for a system that you want to be running 24/7 for as long as it remains profitable.


OK, that's all fine and dandy with a regular CPU, but in the case of a regular CPU, just one error can be enough to freeze the system and force a reboot.
- these ASIC's seem different. They are much more forgiving of errors and will happily continue to try their calculations even if they get half of them wrong, lol./

-- the thing I'd like to determine, is whether or not the HW error rate is parabolic? (I would expect that it is, from prior experience)

BUT  ...
There is a chance that when dealing with so many chips, it may be possible that only a few chips are giving HW errors and that you may be able to reach much higher clock speed and effective hash rate by exceeding the arbitrary limit set in the -auto function of the firmware. Conversely it may be possible that reducing your clock speed by only a small amount could result in a drastic drop in HW errors and effectively give you a higher accepted hashrate.

The only way to know for sure is through thorough testing. Every device, every chip will respond slightly differently. This is why I love overclocking. except ram timings, don't even get me started on ram timings  

This is how I did it. (was confirmed by CK to be a sensible way to determine your individual device's optimum speed)

- make sure that you have some free time and that you can actively monitor your device for the next hour or two (not necessarily mandatory, but prudent)
- in the cgminer configuration tab, in the "more options" window, enter --avalon-auto and save and apply (personally, I usually do a hard boot after this, just to be sure)
- watch your chip frequency climb. (I'd recommend refreshing to check your speed and temps every 10 minutes or so. The software is designed to find a sweet spot where your speed is high and your HW errors are at an acceptable rate. It is not mandatory to actively check, but anything is possible and neither myself nor ckolivas are responsible if this sets your avalon on fire  )

- after a while your frequency should settle into a certain range (for me this was around 349-351)
- at this point you can remove the -auto command and just put in whatever clockspeed you deem reasonable (I recommend you set your clock a little lower than where the -auto setting started to level off. Personally, I chose 345 to give a little breathing space.)
- reboot your device to ensure that the new settings are applied and you should be good to go.

A couple notes:
- this will likely reduce the lifespan of your Avalon.
- there is always a risk involved in running a chip beyond its designed specifications.
- make sure you continue to monitor the temperatures and your accepted/HW error ratio - it is possible that a lower clockspeed may result in less HW errors and effectively get you a better score at your pool. I recommend watching the reported speed on your pool closely to see if it starts to decrease for an extended period (this number will likely fluctuate greatly, but if it continues to drop, better check your speed)

Again, I take no responsibility if this fries your Avalon, and it will most definitely void your (non-existent) warranty.

Have fun!