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https://i.imgur.com/XfNyj76.png]

Batch 2.  Active cooling + overclock. Each tweak I apply bumps the GHash.

Now I'm shooting for 100Ghash/sec. Who is with me?

Bravo..

Holy crap. Very nice work !

STFU...!

EDIT: Congrats, my jaw hit 'save'

What clock speed is it?

Wow, that really changes the bang for the buck equation.
What does that do to the temps and power draw?

Judging by his previous posts, he has an A/C unit that draws as much power as the Avalon itself blow cold air into the intake:

http://imgur.com/dJSUjvg.jpg

Yes, but look...it's battery powered!! ;D

On a serious note, you say stable, but the average is stated as 85 Gh/s, so how long has this unit been 'stable' for?

quite impressive. I'm planning to do the same thing with a very similar looking AC unit.

Question: did you upgrade the PSU? and if so, what are you running now? and if not, can you verify the make/model of the PSU that came with your avalon?

Thanks

https://i.imgur.com/SQANizl.gif

Congrats.

Is condensation an issue at all here with the AC cooling it? Just curious.

A fine solution if the additional 20 GH/s is earning you more than the increased power consumption. Curious though how sustainable this is unless it is a 4 blade unit?

I've had my AC unit blowing directly at my 3*7970 for over a year now, never had a problem, but in the summer, the AC can barely keep up... temps are getting over 80 C on hot days.

Have anyone tried to completely submerge Avalon into mineral oil? That works very well for desktop computers.

Fluid would be too viscous for the fanz...;)

I wonder if there is a water block out there that would fit...
100GH/s with good cooling, might be worthwhile.  ;)

I've got a system that's submerged in mineral oil (quad E5-4650).  Transformer oil to be specific (lower viscosity, higher flash temps, mostly synthetic, no PBAs).   Fans don't really care, although that's not the primary circulation method (pump).

congratulations

I'm also curious if you are running the stock PSU.

Part of air conditioning (heat exchange) works to cool the air cools by removing moisture.  Static electricity would be a bigger risk than condensation... the condensate accumulates on the coils of the A/C unit and (hopefully) is removed by some method (a drain?).

Static electricity does have a tendency to be worse in dry air and is a bigger risk factor IMHO.  I seem to notice this more in the summer months of air conditioned server rooms.  Although I am not sure an R2D2 unit such as that would cause any concern for overly dry air and static electricity.

was wondering how long it'd take people to notice ( and more importantly share the constant that we've released on github.)

the number you are all aiming for is 450 :P of course, that's not really possible on just air cooling.

You mean is possible to hit 450gh/s no kidding? not possible just on air cooling, you need heat sink plus
liquid cooling?

Do you think that the batch 1 design power distribution can manage the increased power draw at those speeds?

Wow, somebody needs to start selling custom Avalon water blocks ASAP :D :D :D

Am in the process of making one when my unit arrives and ill be selling them to people but a fair bit of that still waiting on batch #2

As I recall, I remember telling you to try 90+ gh/s this morning.   ;D


Congrats man.  And yes I believe 100 to 120Ghash/sec is attainable.   Just make sure your A/C does not auto shutoff because it sense's your  "Room" hits X ammount of degrees target.

Mine did.

:/


All is well.

What is the chip capable of 350 Mh/s or more?

He probably means 450 MHz / chip

My quick math (could be wrong) estimates the Avalon should be able to hit 105-115 Gigahash/second at ~450mhz clock.

originally at 282mh/s  overclock to 450mh/s is 62.6% increase?

I've got a feeling we're going to see some interesting K16 cooling solutions being created to get more than 4.5GHs out of each unit...

Psst... ask Zefir... he has a design I believe that will be shared open source for a water block. Given that the Avalon seems to be right as rain with some great numbers should be great for Klondikes.

 
I have once created a cooling block design for the Avalon miner.
Sadly i never got my hands on a Avalon in time.
So if anybody would be interested, tell me.

I will create a waterblock for zefir as well soon.
Might help to boost the chips performance.

Has anybody got to know yet how the 300 Mhz boundary limits of the Avalon work and how to trick it ?

I'm sure there will be lots of interest. I just e-mailed the plans for a water block posted here (https://bitcointalk.org/index.php?topic=211825.0) to a machinist I know to see if he can build them locally but I would pay good money if there are any other options out there.

What I find bizarre is that Avalon chips are able to hit 450Mhz with liquid cooling on plastic packaging.

What then would these chips hit in terms of clock if they were packaged like BFL's?

I can't help but wonder...

And gen 2....will be....worth watching....

might try putting my upcoming BFL units in mineral oil too.
 8)

You are a clever, clever man.

What is the limit when we approach these speeds, the chips, the boards, the power delivery (ignore PSU) or the cooling?

Cyanide idea

How did you overclock it in the first place?
Thanks,...

Good idea, transformer oil must be better for sure. I want to setup some cooling solution for miner while its not delivered yet. Do you use some sort of a radiator to cool the oil itself? I would not be comfortable with tank full of overheated oil in my room :)

*lol* 450MHz... and with such "old" technique. I calculated KNCMiner to be half the price (including vat) per GH instead using avalon chips + assembly. Now with this overclocking the advantage of KNCMiner is gone, taking into account the longer months until the miner can be received. BFL is fully out of the game and the their credits are worth nothing. And since the GH of bitfury is similar to kncminer its the same there like with kncminer.
Of course it has to be shown whats the overclocking capability of bfl, bitfury or kncminer chips. But its a bit funny that the old technique is nearly as good as the new one. Probably there is a reason why avalon and bitcountain chose to take the old techniques first.

This is definitely a game changer if they run stable at that rate.

Nice. I've been wanting to do this to a computer for a while (I think my i7-2700k would over-clock like a MoFo.)

I'm pretty sure I'll be trying this with my K16 boards. Where did you source the mineral oil, if you don't mind me asking? Also, what type of container are you using? I've seen debates on using a plexiglass enclosure, and possible ill effects on it from the mineral oil.

Thanks

This is a concern, normally for overclock you need strong power supply module, not just only a large PSU. Someone already burnt one of the hash submodule even under 282Mhz, but that could be caused by a bad component. Anyway, I found out that hash rate tends to jump between 50Gh and 100+Gh wildly when heavily overclocked (350Mhz), not a good sign

I'd love to join you, but I don't got anything to shoot with!  :'(

You're forgetting to overclock when running the AC ;)

What happens if you replace the original paste with Artic Silver 5 or other similar compounds such as high quality thermal pads?

AS5 is conductive, if it flows back to the chip through those small tunnels, who knows what will happen. MX4 is non-conductive and also cheaper if you want to apply for all 240 chips (a 20g tube is enough)

Any positive benefit to applying MX4 on the chips?

Congratulations

https://bitcointalk.org/index.php?topic=211825.0

Is there enough spacing between the modules to put gpu ram sinks on each individual chip? I have about 2 kg of them, yes kilograms  8)

Infact just checked how much the bag of them weigh, it was close to 4 kilograms so I should have plenty for 1x3 module avalon once I get it.

Has anyone verified that 98GH/s is stable 24/7?

I think the highest people have gotten stable with stock B2 is 350MHz ~ 84GH/s on 3 module system.
98GH/s on a 3module system is ~410MHz which I don't think anyone has been stable on.

98GH/s on a 4 module system is ~310MHz which should be fine.
I don't believe that MagicMike523 has stated in this thread what frequency the chips are running at or how many modules.

My guess is that the 98GH/s is lucky variance with a 3 module running at 375MH/s ~90GH/s with some lucky stability and lots of cooling.

Water cooling? Mineral oil? Just wrap the blades in applewood smoked bacon and enjoy a slower but tastier Avalon!  :P

Mmmm...nom, nom, nom.

I was thinking people should replace the thermal compound used in the Avalon unit. Considering there are some people who found out some units have no thermal compound or had it improperly applied.

Assuming that the thermal compound is crap and/or low efficiency, then transferring the heat from the chips to the heatsink would probably help some at higher clocks. A good number of thermal pads with 6 or 7watt/mk should help alot if this is the case. (It would be the equivalent to MX4.)

The next problem after that is how (in)efficient the heatsink actually is at discharging the heat with the current design.

Then finally finding an air temperature that allows the heatsink to work at a reasonable pace. (not too cold because it costs $$$ to keep it at that temp)

etc

Yes thermal pads would have been a better solution on such a large and uneven surface I'm quite sure. I'm still curious however to see how much individual heat sinks on the chips would make since then you don't have remove the original heat sink. Might take a while to apply them all though  ;D

https://en.bitcoin.it/wiki/Avalon#Others

"About install extra heat-sinks on each avalon chip: please do not do that. there is a air gap between the die and package top, install a heatsink on chip is useless. and will cause overheating. because the top PCB copper act as a heatsink too. do not cover them. " --NGZhang

The exposed metal area under the chips are shallower than the surface of the PCB, if you put a large piece of heatpad then maybe there will still be air gap between the metal part and heat pad, and you can't guarantee a good pressure on all the chips' contact area at the same time, so I think thermal compound is the solution: You put one big drop of the thermal compound on each metal area, and tighten the screws, the thermal compound will spread out depends on the gap distance between chip metal area and the heatsink, so that every chip will get a good contact with heatsink

http://avalon.mystisland.org/inside2.jpg

The result of this handling is reduced temp of 3-4 degree under same fan speed, but since fan speed will always adjust according to temp3, the real effect is just lowered fan speed and maybe 1 degree lower temp. Anyway, you can be sure each chip get maximum cooling now. Then you can also add thermal compound between heatsink and bottom of the case, and cool the bottom of case with an external table fan, this can drop another 3 degree of temp

Another important part is putting screws around VRM area, there is a very hot component at this area, MOSFETS maybe, but not like chips, this component only contact the surface ground layer of PCB, so adding screws will transfer the heat from the surface ground layer directly into heatsink
https://en.bitcoin.it/wiki/File:Avalon-IR-1.jpg

Since Avalon heatsink are so large, maybe it works even better by taking out those modules and use a large table fan to directly blow on them, or mount many 120mm fans on heatsink like someone did on ASIC miner blades, as long as you reach a certain CFM, the cooling effect should be the same. I usually like the bigger fan solution since it will provide much more airflow and much less noise

Thanks for the images.

I was actually thinking of cutting the thermal pads into squares rather than using a full sheet like a blanket. I have no clue yet what the thickness of the thermal pad should be. (.5mm > 1.5? (in increments of .5mm)

Ah, I hadn't actually thought of doing that. That is a pretty good idea.

So far I have been hesitant to change anything of the stock configuration. (I am not the "tweaker" kind)

I have only placed a strong laptop fan towards the bottom of the Avalon Unit to increase the heat dissipation of the bottom aluminum plate where the modules are connected.

Did that lower temps or reduce the fan speed?

Someone with a restaurant job needs to try running one of these in a walk-in!

This Avalon is for sale. Asking 190BTC/shipped.

Is it still working ;D

And ROI tends to be infinity?

Good luck to the happy buyer and pls  french fries for free also

My avalon (batch#2 black) have one big black thermal pad, so no thermal compound. It's really bad to remove because it sticks on the screw holes. I did it with one module and added artic mx2 one all chips. But it was not helping much to get higher clocks.

Better would be to add/drill all the holes, because the small modules do not get good "pressed" on the heatsink.

I have good temps without AC: 16 / 33 / 36 @ 355 --avalon-auto after 2h

If i go 365, same temps but 3,4% hw rate. Is it the PSU that prevents higher clocks? I run the stock 750W. Well i will test a 1000W PSU i have spare.

greets,
ebereon

Anyone feeling dare devilish and want to make a volt mod to the avalon chips with custom cooling and get these bad boys running at 400 mhz??

I guess it is TPS power converter and to much noise in avalon chips power. Just a guess. At that clock TPS my be driven at abot 90% of it's capacity. I am still waiting for someone to measure accurately chip consumption at 1.2V when overclocked.  

Congrats Mike! It is looking good :)


This is first good information for batch 3 customer form long time, maybe this will help achieve break even, but now it will be good to get nice water cooling :)

Because I have a small brain, I am not clear what this means:


Is the 450 value clock speed, MH/s, GH/s??? Is that value for a 3, 4 card Avalon unit, a per chip over clocking value or a per chip hash value?

The discussion in this thread seems unclear.

Per Chip. It is the frequency. 450 MHz. But from overclocking 282 MHz to 450 MHz this would be a sick overclock. Even with active watercooling i.e.

O.o But good luck!

Thanks Silv0r.

Are there any reliable estimates for amp/power requirements at that speed (within a tolerable range)?

Oil. If not with an Avalon rig... you will see it with a Klondike or something similar.

Just to sum up things just to make sure I understand it well ...

Assuming I am able to cool it down properly (server housing room with low temp), what is possible with the very default batch #2 Avalon? It's default clock is 300. Would it be somehow dangerous with the default PSU to try to overclock it? If I set the conf to 300 and range 300-350, should it handle it?

350 should be *safe* out of the box on the Enermax PSUs. will net 82-83GH. Anything more and I think we're waiting for the volt mods to be honest.

I am running active water cooling - netting around that. Cooling is not the issue for getting beyond that any more.