Xeon PHI 31S1P

[Perri__Pierpaolo]

Hi all guys,can anyone suggest me an active cooler for a Xeon 31S1P1?Is it worth to buy the heat sink of the 3120A,and is it possibile to buy it from Intel?Thank you so much...

[Perri__Pierpaolo]

Hi Mr. Dempsey,this is my last release of my "dissipator"...after one hour,without workloads, these are the temps of the two cards.What do you think about it?What are your the temps of your cards?

Regards.

[Perri__Pierpaolo]

Creating simple workload in MATLAB:the power of a matrix,10000X10000 of  double, A^35...the calculus is distributed over the two cards,all their cores are active...

https://dl.dropboxusercontent.com/u/68372933/MATLAB_PHI.JPG

[jimdempseyatthecove]

It looks like you have the cooling problem solved.

Jim Dempsey

[Perri__Pierpaolo]

...but the solution is very loud!I would have preferred a liquid cooler...

[AWeis7]

Where did you get the plastic duct, and what was the part number? I made a duct out of foam board, and it appears there is sufficient air leakage such that I'm not getting effective cooling, even with a fan that is rated at 70 CFM.

[jimdempseyatthecove]

Pierpaolo,

My system is louder than I would like, but it is not terribly loud. It is not even uncomfortably loud. I used to have a 1U server (without MIC) and that was horrible for use in an office. The system with the MIC's is about as noisy, or less so, than the HP LaserJet4 Plus printer sitting next to it when printing.

Consider using something like this: http://www.newegg.com/Product/Product.aspx?Item=N82E16811997117&cm_re=fan_controller-_-11-997-117-_-Product

Jim Dempsey

[Perri__Pierpaolo]

@neonator
The duct is part of "nexus waveair",but the most important thing is to use a fan with a high static pressure,I used a couple of these...also if they are loud to me! :)
http://www.digikey.it/product-detail/it/FFB0812SHE/603-1057-ND/1014388

@Mr. Dempsey
...thanks,interesting stuff!

[jimdempseyatthecove]

I have the 5110P which have somewhat less cooling requirements than the 31S1P.

parameter mine        yours
size      70x70x25mm  80x80x37mm
speed     3400RPM     4900RPM
AirFlow   34.78cfm    68.5cfm
Noise     <28dBA      48.5dBA

Your real problem is your dBA for your fan

48.5 / 28 = 1.732

10^1.732 = ~54

The amplitude of your noise is ~54x that of my system.

You need to need to locate fans with sufficient airflow .AND. at lowest dBA

Jim Dempsey

[jimdempseyatthecove]

With a little bit of searching I found this:

http://www.newegg.com/Product/Product.aspx?Item=N82E16835132020

80x80x25mm, 62cfm, 39dBA

48.5 / 39 = 1.244
10^1.244 = 17.5

about 17.5x less noisy with only  marginally less cfm

Jim Dempsey

[Perri__Pierpaolo]

I already tested the bblaster 80 and it was insufficient,this because the problem isn't the cfm value but the right static air pressure.Every 80x80x25 fans are not able to produce high air pressure (at least 0.54 in.H2O) only the 80x80x35 are able,but they are very loud...
 

http://www.pugetsystems.com/blog/2014/12/18/Xeon-Phi-31s1p-Cooling-and-Motherboards-614/

[AWeis7]

At the risk of voiding the warranty on the card, I wonder if anyone has taken the blue cover off, cut a round hole in it, and installed a fan over the relevant bits?

Also, how about putting a water cooler on the copper plate, or a radiator/fan combo on it?

[AWeis7]

Or how about just removing the blue cover, and positioning a fan over the relevant bits, no need to even cut a hole. Is this a viable strategy?

[Perri__Pierpaolo]

The dissipator is built so that the air flows through it and not over it...there is a liquid cooling system for phi cards but isn't sold to end users...

[AWeis7]

What is the dissipator? Also, how does the active cooled version work, I've seen they have a hole in the blue cover, with a small fan, what does it blow on, and how much air does it need to move to be effective?

Also, I've seen a full card dual blower., can this be used on the Phi, if the cover is removed?

[AWeis7]

Can I use something like this to cool the card down, assuming that I remove the blue cover?

http://www.gelidsolutions.com/products/index.php?lid=1&cid=17&id=73

[Perri__Pierpaolo]

Neonator, all the informations about the active cooled dissipator(for the other phi cards) are in the 31S1P data sheet.The solution of gelid is not certified for the layout of Xeon PHI,you have to choose a solution that is specifically designed for it like for example this:

http://asetek.com/press-room/news/2012/asetek%C2%AE-liquid-cools-intel%C2%AE-xeon-phi-coprocessors.aspx
 

unfortunately that is not sold to end user only to oem!

[Perri__Pierpaolo]

...and if you find a good active cooler for 31S1P,please write here!...my solution is horribly loud!I have to use my PHI workstation only for testing,intensive calculus and debugging purpose,I had to move the development on another pc! :(

[jimdempseyatthecove]

Pierpaolo,

Have you checked to see if your inlet temperature is too high (this is the temperature of the air being sucked in by the fan). This is the inside the case temperature.

In looking at the picture, above the temperature screenshot, it looks as if the outlet for the fan is significantly smaller than the inlet for the airflow into the 31S1P. By my eyeball estimate, your outlet is 2/3rds the area of the 31S1P's inlet. This will cause a constriction in the airflow, thus requiring a higher "head" (higher pressure) to attain the same airflow. This may be one of the reasons as to why you need such a forceful fan.

Jim Dempsey

[AWeis7]

I looked on the data sheet for dissipator, do you mean the heat sink or the fan? See page 20 on the data sheet:

http://www.colfax-intl.com/nd/downloads/Xeon-Phi-Coprocessor-Datasheet.pdf

I had contacted asetek in Dec, they wouldn't sell me the Xeon Phi cooling solution outside of their overall cooling system. This doesn't make sense to me, they have standard fittings on it, and they have a DIY system for the NVidia cards, so these could seemingly be combined.

When I look at the diagram on the data sheet, it appears that taking off the cover, and perhaps blasting a fan directly on the heatsink might provide enough cooling, have you tried this?

[jimdempseyatthecove]

Your solution is providing airflow between the red lines, my solution is providing airflow between the blue lines.

Pay particular attention to the fact that your solution is not blowing air between the bottom red line and the bottom blue line.

From the datasheet:

In order to ensure adequate cooling of the SE10P/7120P/3120P 300W SKUs with a 45oC inlet temperature, the system must be able to provide 33 ft3/min of airflow to the card with 7.2 ft3/min on the secondary side and the remainder on the primary side. The total pressure drop (assuming a multi-card installation conforming to the PCI Express* mechanical specification) is 0.54 in H2O at this flow rate.

You are not providing any airflow to the secondary side.

My comment #20 addressed this very issue and included a suggestion as to how you can fix it.

Jim Dempsey

[AWeis7]

Hi Jim,

My case has a fan in the PCI bay, that supposedly moves 35 CFM.So, I am looking in particular to get cooling in the red area. Isn't this what the active cooled Phi cards do, there is a fan inside the case, that is moving air across the heatsink.