Restructuring cooling capacity for Avalon

[PuertoLibre]

 

I am about to buy some Fan upgrades for my Avalon but I need some advice.

I have settled on three of the Gentle Typhoon series (5400rpm) of fans which seem to have better static pressure and more airflow (CFM):

http://www.scythe-usa.com/product/Case%20fan/001/Scytheusa-ProductsgentleCaseFan001index.html

I need some advice though on the internal setup. The Gentle Typhoon is a 3 pin fan. The power for the fan is being pulled from a molex connector via the PSU. So power isn't the issue, fan control is. I have been looking over the photo's provided by Avalon for the control unit:



I noticed that the unit has 5 headers and they all seem to be 4pin. I know I can just connect the 3 pin into it. What I don't know is if this simple board does any kind of voltage regulation for 3 pin fans?

I realize PWM was invented because you could modify the RPM by a signal rather than by a voltage such as 3 pin fans had been.

So my first question is, Does this control unit properly apply 3 pin voltage regulation for 3 pin fans?

-----------------------------

My second question is: I believe that 2 out of 3 fans used in Avalon Batch 1 were PWM enabled Deltas. Any idea whether the third (transparent fan) is also PWM or if it is a standard 3 pin fan?

I intend to overclock this Avalon and I want to minimize the risk from overheating. Can anyone who has taken apart their Avalon (batch 1 & 2) please fill in the gaps for me on these particular questions?

[dogie]

You do realise those fans are SIGNIFICANTLY louder than the stock, to reach the same performance?

[PuertoLibre]

@ Dogie

Actually, they are about the same:

50db (Avalon Stock) vs 50.5db (Gentle Typhoon 5400rpm)

https://en.bitcoin.it/w/images/en/8/88/Avalon-fan.jpg

Specs:

http://www.nmbtc.com/fans/part-numbers/DC-Axial/4715KL-04W-B56/5267

The static pressure on the Stock Avalon fans are actually lower. So is the CFM.

------------------------------

Regardless, the RPM's is what I am trying to control. If I don't have to put in a fan controller it would be the best solution. Anyone have any clues as to the questions above?

[GenTarkin]

Just get those 5500rpm HP server fans =P
they do 252CFM...
TFC1212DE

But will have to use firmware that has inverted PWM Control...
These fans eat about 50watts a piece at full RPM .. rofl...

[-ck]

Unless the fans you choose specify PWM, then there's a good chance that even if you can get them to connect, they will not spin correctly with PWM control. Fans need to be designed to work with PWM because of the way it works since it pulses voltage to them rather than decreases the voltage to them. You will be hard pressed to actually do better than the stock fans (the 38mm NMB ones).

[GenTarkin]

Unless the fans you choose specify PWM, then there's a good chance that even if you can get them to connect, they will not spin correctly with PWM control. Fans need to be designed to work with PWM because of the way it works since it pulses voltage to them rather than decreases the voltage to them. You will be hard pressed to actually do better than the stock fans (the 38mm NMB ones).

Someone in the avy users thread wrote PWM control fork for avalon & specifically the fan I specified =)

BTW do you know what the ratings are on the stock 2 more powerful fans in batch 2 unit?

[PuertoLibre]

Ah,
I investigated that fan, it was quite (excessively) powerful.

The problem is, I don't know if that particular fan comes with a molex connector (due to the heavy power requirements it probably should!).

The final problem is that I wouldn't know how to compile the fork for that particular firmware. Unless it is already precompiled somewhere?

Any idea where I could buy this fan from? (If It doesn't work for the Avalon unit, I'll put it to other good uses.

[candoo]

the Scythe comes with a molex connector and If you are clever, then just give him 12 Volt and let him run at 100% 24/7

[GenTarkin]

Hey puerto .. what about this fan, it may fit the bill:
http://www.heatsinkfactory.com/delta-afb1212she-cf00-120mm-ultra-high-speed.html

bunch more options here too:

http://1stpccorp.com/fan_delta_120mm.htm

mmm... this one looks yummy:
AFB1212GHE-CF00
http://www.newegg.com/Product/Product.aspx?Item=N82E16835213001

[PuertoLibre]

Hey puerto .. what about this fan, it may fit the bill:
http://www.heatsinkfactory.com/delta-afb1212she-cf00-120mm-ultra-high-speed.html

bunch more options here too:

http://1stpccorp.com/fan_delta_120mm.htm

Ah, looks interesting.

Does anyone know if the Avalon unit will startup if the fans remain disconnected from the system? (Perhaps bypassing the internal controller is a better idea?)

[GenTarkin]

Hey puerto .. what about this fan, it may fit the bill:
http://www.heatsinkfactory.com/delta-afb1212she-cf00-120mm-ultra-high-speed.html

bunch more options here too:

http://1stpccorp.com/fan_delta_120mm.htm

Ah, looks interesting.

Does anyone know if the Avalon unit will startup if the fans remain disconnected from the system? (Perhaps bypassing the internal controller is a better idea?)

Well the guys that made the water cooling setups Im sure figured that one out.... but not entirely sure ...

[GenTarkin]

haha watched some vids of that fan, it fuckin takes off on a table at only like 20% RPM.. it hovers itself half - full speed .. ROFL!

[invader]

Does anyone know if the Avalon unit will startup if the fans remain disconnected from the system?

Yes, as i said previously there is no protection when the fans is going to zero rpm, essentially the same as not connected. Only safety feature is default 60c temperature cutoff in cgminer now.

The final problem is that I wouldn't know how to compile the fork for that particular firmware. Unless it is already precompiled somewhere?

Already done, using it near a week with no problems.
I'll just put it on github or somewhere else later i think.
Constant AVALON_FAN_FACTOR also needs to be re-adjusted to return correct rpm value for "non stock" fans.
One more option needed for that, but it's very easy.

[dogie]

@ Dogie

Actually, they are about the same:

50db (Avalon Stock) vs 50.5db (Gentle Typhoon 5400rpm)

https://en.bitcoin.it/w/images/en/8/88/Avalon-fan.jpg

Specs:

http://www.nmbtc.com/fans/part-numbers/DC-Axial/4715KL-04W-B56/5267

The static pressure on the Stock Avalon fans are actually lower. So is the CFM.

------------------------------

Regardless, the RPM's is what I am trying to control. If I don't have to put in a fan controller it would be the best solution. Anyone have any clues as to the questions above?

Paper specs recorded by manufacturers aren't trustworthy. Think of it this way, 42mm v 25mm, server class v enthusiast.

[johnyj]

GT 5400 RPM does have a PWM signal input, you can either get PWM type of fan or do some manual modification

I got a 192 CFM delta pwm fan, but the noise is not acceptable above 2500 RPM, so in general 120MM fan could not be much better without too much noise, if you want to get higher airflow, better use a 40cm desktop blow fan directly blow into the box, much less noise and more airflow 

[GenTarkin]

Does anyone know what the avalon fan controller can handle current wise?

[Wayne_Chang]

Who knows the limit temp of Avalon chips? The stock fan is too noisy for me. I prefer to change to some quieter fan by sacrifice some hash power.

[GenTarkin]

update on the 240CFM fans I ordered....
So, didnt realize the avy PSU is modular and that they didnt leave any molex leads in there ... So had to route my new fans to another PSU outside the avy...
Anyone know where I can get the modular cables for the avy PSU? I have the enermax GX850...
if not, anyone know where I can get a 6pin PCIE -> molex 12v only?(there is one extra pcie connector in there)

So, overall the fans have dropped degrees by 10-15C @ 350mhz
The modules run much cooler @ 350 on a hot day thus far. And have been auto clockin to 352+.... lower HW errors too by a bit...good stuff.
I have the RPM sensor of the fans plugged into avy fpga board and senses them fine @ 5280rpm each.

They are loud tho, can hear the avy through my garage window, through the patio door, into my place on the opposite end in my bedroom....ROFL!

[A Meteorite]

Who knows the limit temp of Avalon chips? The stock fan is too noisy for me. I prefer to change to some quieter fan by sacrifice some hash power.

Up to 50C is generally considered safe, although the chips are rated for higher than that. But higher than that will probably mean more HW errors.