Topic: [ANN] Spondoolies-Tech - carrier grade, data center ready mining rigs - page 517. (Read 1260354 times)

Get a hot air extractor at the one side and a fan to push air in at the other.

Just look at some growshop websites to get the idea, they have everything on hand needed for ventilating hot rooms  .

ok i'll try to do it your way....use something like this to get air moving over the unit ...so to speak

http://www.menards.com/main/fans/commercial-fans/stanley-blower-fan-pivoting-utility-fan-with-grounded-outlets/p-1393859-c-12728.htm

so what put a duct behind the Sp30 and just duct it out like a clothes dryer to the outside of the house (thru window?)

that kinda thing?

again with like 4500 watts of heat being made in my bsmt ..i still think it is likely i'm cooling with the a/c window unit the damn room  down and blowing hot air out as fast as possible
thru duct/window on at least the sp30 unit....and even have other fans plus the one above around the bsmt to still keep it moving out ..the air that is again I can see 10-15 days august/sept where I may have no choice...worst case senario

hope folks are correct about just moving heat out...but somehow I kinda expect at least for some days (say 15 or so) i'm gonna be closing the door..in the room
pumping a/c in and blowing heat out as fast as possible just to keep the sp30 running more/less...this is why I'm gonna over kill with the a/c unit ..should it be
overkill rather have it in if i need it then have to mess with it after the miners trickle in

again hope I'm wrong ...but seeings how I really really bit off more then I can chew with a Titan (aug) and sp30 (sept) well on a plus note come end of sept
or oct i can use the heat for the house (thus why i did not host...also hosting cost as much as elec before shipping/setup costs etc)...so went with this...

anyway why I got myself into this 'somewhat interesting situation"

good to have goals I guess

I'll put photos up so everyone can roflao at my kludged up hopefully working setup when all is done

by the by spondoolies-tech do you have any advice for me... besides me being out of my frigging mind for not putting both the Titan and the Sp30 in a data center?

I'll take any abuse for some advice....(will likely get a reply ..don't give us your name or we will void your warranty before we ship you the Sp30 as there is no hope)

FML

Searing

ps here are some pics of my unit and the large block basement walls also a pic on how my knc juptier arrived full of rain water heh

http://lostgonzo.imgur.com/

The chips DO NOT NEED to be that "cold".

If you calculate the cost of using 20-30% additional electricity and the cost of buying an AC, you will quickly discover that it is just not worth it for a small possible 5% performance increase.

You either already have very low ambient temperatures and can either settle with lower airflow or increased airflow and better performance, or you dont.

It is not economically viable to cool the air down in your mining room, if you can have enough airflow.

Is the needed airflow in the mining room not the same as the air flow in the miners?


It's not irrelevant because if you want max performance you need cooler chips.

The only two variables that miners have control over is air flow and air temperature.

For some people it's just not possible cool the chips down to ~90C if the dT between the chips and the air is 40-50C. (Without an AC)

TSMC 28HPM process has much lower leakage than 40G process. For instance the same 2-input NAND gate using standard Vt transistors in 28HPM has 5 times less leakage. This ratio is consistent for most of the cells. The leakage is maximal at high temperatures effectively doubling every 10C-20C. In addition to it 28HPM has more transistors options with smaller Leff transistors for higher speed (and higher leakage) and higher Leff (slower but less leaky) which can be used for lower speed parts. Smart mixing of all different available Leff sizes allows additional leakage reduction while increasing speed.

btw:
AM (BitQuan) still didn't tapeout their 28nm effort. Long wait until dividends ... 

It is all that matters because you are only calculating the needed airflow for your mining room, not the unit.

Those calculations are done by the engineers designing the unit and therefore irrelevant for the average miner.
Spondoolies have done those and designed the unit accordingly.

What do you mean it's all that matters in this setting?

You could have a shitty heatsink or even no heatsink at all and still manage an in/out air dT of 11C with 150cfm. (assuming the chips don't explode at 500C)


I think this is what you're looking for:

http://en.wikipedia.org/wiki/Heat_sink#A_heat_transfer_theoretical_model

We can only guess the variables but I just don't understand why they would go with a 2u case/fans with minimal heatsinks considering most DC's can't even cool such high densities.

Why not use a 4u case with 4 250cfm fans (or quiet 150cfm fans) and much larger heatsinks?

Yes, the quoted values are only valid for "cooling" your "Datacenter" room and the temperature difference is between intake and output temperature of the units (which is all that matters in this setting).

Calculating the needed airflow for individual miners is much more complicated as you also have to take into account heatsink area aswell as various other factors.
It is also the responsibility of the engineers designing the miners and cannot be influenced (too much) by the customers.

Source for lower leakage on 28nm? I've only heard it gets harder to cool smaller process sizes.


You are talking about dT between the intake and exhaust air right? What is more important is the dT between the chips and the air.

Even if the in/out air is only 11C dT, the chips near the exhaust will heat up to ~100C (40+11+50).

I will put up a window a/c unit in bsmt 'just in case" but i have the old limestone bsmt 12' walls with 5 (small) scattered randomly small usual bsmt windows like 19" by 28" or whatever.

so i aggree but what would i need for air flow at the windows to move all this heat out...imho it likely is just moving hot air out for hot air in on the days i suspect the a/c unit is only hope

i hope to do as you suggest but clueless on how to get enough wind over the unit and up and out you old gpu guys what did you do?

I have to move about 4500 watts out in some manner and/or on the really over 95 humid days of august (say 12 days or so) use a/c and still move hot air out as a backup

suggestions on window fans

also what about bugs the fans I see that move this kinda air for turkey barns lifestock no screens shutters or w/o shutters so how much heat can i get out blowing out of my
basement with out blowing the screens off or filling house up with bugs (still got to live/sleep there ...other reason miners are in bsmt)

Searing

The sp30 should be less sensitive to higher temperatures due to the following reasons:

- 400cfm maximum airflow aka ~45% higher airflow per kW
- lower leakage increase on 28nm vs 40nm at higher chip temperatures
- roughly the same heatsink surface area per kW than sp10

As to the cooling questions, it is roughly  q=wCpΔt which means:

→ 157 CFM are required to cool 1 kW, if the ΔT through IT equipment is 20°F (11°C)

→ 125 CFM are required to cool 1 kW, if the ΔT through IT equipment is 25°F (14°C)

→ 105 CFM are required to cool 1 kW, if the ΔT through IT equipment is 30°F (16,5°C)

So temperature is equally important than airflow, however increasing airflow is obviously much easier (and therefore cheaper) than lowering the temperature.

80-95, but heatsink deltas will probably be 40-50.

400cfm is really not much for 2.6kw.

20C dT is good even for high end heatpipe heatsinks with ~100cfm fans per 150w chip.

Anyone know the actual temperature difference between the chips and intake air for the sp10?

40C ambient with lots of wind = 60C at silicon
40C ambient with little flow = 90C+ at silicon

40C ambient with very serious airflow = even less than <60C

air flow is VERY cheap
air conditioning is very expensive. 

Yes semiconductors love 40C. But you don't get anywhere near 40C with air cooling. The tempurature difference between the ambient air and the asics is the real killer. I would guess the dT is more than ~40C.

Semiconductors love 40C - people hate 40C.  

Even if your ambient is 50C - with shitloads of wind, your ASICs will be fine.  Heat is not the problem miners face.  Heat accumulation is.  Vent out the ceiling and blow, blow, blow.  An AC is a horrible way to move heat outside. 

I agree with you, been running 3 Antminer S2 and 8 Anminer S1 in my basement in an unfinished side, I have bunch of fans blowing the air away from the miners, Ambient temp is around 98 F, I am in NJ and been running them for about 3 months now without any issue but the kitchen feels like we have radiant heat.

No shit.

A simple mnemonic formula: [degrees (F)-32]x5/9=degrees C
Personally, I am bi-temperate (as per bi-lingual) so to speak due to personal history, so it does not matter to me, but i've seen people burning their fingers in a water bath that said 70o (they thought that it is in Fahr., but in scientific establishments everything is in C).
So...37.8oC-better than in a sauna, but anybody has difficulty coping without A/C.
Not the worst-that is Arizona at 116oF or middle east at 120-122.

The math to get you to C isn't extremely hard.  If you practice a bit, you'll get the hang of simple algebra after a few weeks.  Some people might take a bit longer


In the present case, you can ignore algebra and just use an estimation.  Everywhere you see '100' above, just put in '40'.  You are good to go!  The statement still makes great sense

I live in Europe.  I prefer C.  But when I see F, I don't cry.