Poor results with Scythe Ninja ??

[Zim]

I bought a Scythe Ninja and a 120mm Thermaltake Smart Case Fan and installed them in my system (see sig.) expecting great things. It wasn't easy to install because the fan was hitting the memory dimms, but I got the fan fitted further up the side of the Ninja a little. To my disappointment, the results were identical to the my Thermaltake Venus 12: about 28C idle, and 54C at full load. I was hoping to pull down the load temp, but no such luck.

I remounted the Ninja twice (with AS5) and am satisfied it was fitted right. The thermal diode for the fan didn't seem to work because the fan never budged from about 1300rpm. However, I noticed that while the CPU temp was reading over 50C, I could not feel any noticeable heat at the base of the heatsink (i.e. where the diode was attached) - I would have expected it to feel warm.

Anyone any ideas what's going on here?

 

[keldog7]

Max current of Opteron 165 is 80 amps. At default voltage (assume 1.35 Vcore), that works out to 108 Watts - within 2 watts of AMDs spec of 110 watts max thermal output of Opteron 165. You have increased that voltage to 1.45V, based on the specs in your post. Your "overclocked max thermal output" should therefore be about 116 watts.
If you head over to www.silentpcreview.com, they give an estimate of the increase in temperature you can expect for every watt produced, specifically for the Scythe Ninja. Of course, it is given in the context of RISE in temperature, so your MAX temperature can only be interpreted if you tell us how hot the case air gets under full load. Also, the amount of air your fan is providing will not match the silentpcreview figure unless the CFM off the fan is identical to their methodology...BUT...
If you use a Nexus 120 fan at about 1000RPM (12V), it provides roughly 42 CFM of airflow.
That much airflow should *roughly* allow the Ninja to provide a rise in temp of 0.19 degrees C / Watt (your CPU has a much higher max power, so the result may not extrapolate perfectly, and I suspect that the rise delta for an Opteron will be closer to 0.17...but thats just my speculation)

In my P180 case, under load, the ambient temp is 27 C.
I use the Ninja on a Opteron 170, with Vcore set to 1.425, cooled by the Ninja with a 120mm Nexus at 12V
1.425V x 80A = 114 Watt under max load
114 Watts x 0.19 degrees/watt = 21.6 C - the expected rise in temperature at max load.
ambient temp + expected rise = observed rise (roughly)
21.6 + 27 = 48 degrees C is what I should *expect* the Ninja to give me.
...in fact, I get 46C under full load...(probably a combination of the rise delta I mention above, and the fact that my ambient temp measurement is coming from the edge of the video card, and is actually a bit warmer than case air)

In YOUR case, you need to know a bit more...
1) what is the ambient temp
2) how much air is your fan pushing at 1300rpm
3) what is the C/Watt for the Ninja at the CFM answer to the second question

Once you have those answers, the math is real simple.
-Adrian

 

[NeezyDeezy]

dag nice answer

 

[GalvanizedYankee]

*Tips hat* Thank you Adrian.

Great post, very well stated=easy to understand.


...Galvanized

 

[Zim]

Thanks Adrian . I will do the math later, but based on what you said I think there is something not quite right with my setup. My situation is very close to yours yet my CPU is running quite a bit hotter. My ambient is in the low to mid 20's and my fan pushes about 40CFM at 1300rpm. I had expected to get mid 40C's at load, but instead I'm getting mid 50C's.

 

[kalrith]

I know that we're running completely different systems, but I just wanted to share my experience with the Ninja. With the system in my sig, I never go past 38 load with an ambient temp in my case of 24. My fan pushes 69cfm 2400rpm, and the temperature doesn't change between 2400rpm and 1200rpm. I ran the max heat test on prime95 with the fan turned off and only hit 48 degrees.

So, I guess I'm a little surprised at your temps. I thought that northwoods ran at least as hot as opterons, but I certainly could be mistaken. My temps with stock cooling at the same speed were 33 at idle and 59-61 at load.

 

[Zim]

I got this Ninja as a refurb from NewEgg. Is it possible that it could have leaked? WHat is in those heatpipes... is it water under low pressure or something?

 

[kalrith]

Originally posted by: Zim
I got this Ninja as a refurb from NewEgg. Is it possible that it could have leaked? WHat is in those heatpipes... is it water under low pressure or something?

According to this site, they do contain fluid: "Heatpipes are generally small copper tubes filled with a fluid which has a low boiling point."

It seems possible that the water could have leaked out, especially since it's a refurb.

 

[GalvanizedYankee]

Originally posted by: Zim
I got this Ninja as a refurb from NewEgg. Is it possible that it could have leaked? WHat is in those heatpipes... is it water under low pressure or something?

Lord have Mercy!
So to save a few buck$ you end up testing a referb for the Egg. I bet it is a defective unit
captain space-ball Send it back soon!

To add to what the other link offers go here http://www.heatsink-guide.com/ >Advanced Cooling > Heat pipes=more detailed explaination.

...Galvanized

 

[IvanAndreevich]

keldog7
BS. Opteron 165 @ stock is not even HALF of 108W.

 

[Apocalypse X]

Originally posted by: Zim
I got this Ninja as a refurb from NewEgg. Is it possible that it could have leaked? WHat is in those heatpipes... is it water under low pressure or something?

okay lets all put 1 + 1 together do they equal 2???

 

[Zim]

nm

 

[keldog7]

IvanAndreevich:
Alright then, why don't you explain to me what the 165 really puts out. Calling something BS without explaining yourself is a simple invitation to flame.
I would invite you to explain to me and the group, the intricacies of Ohm's law (which basically dictates the relationship between current, power, potential [and resistance]). Then,maybe you can come up with a thermodynamic explanation of how my Opteron does rise only 20-odd degrees.
My calculations are clearly laid out.
The specs on an AMD Opteron (including the 80A current max, and max thermal output of 110W (at *STOCK* voltage) can be found at:
http://www.amdcompare.com/us-en/opteron/details.aspx?opn=OSA165DAA6CD
I will be the first to "eat crow" if you can find flaw in my arguments - but your post is garbage, and makes me question how you attained the status of "diamond member". In this particular case, I think you should *sit down* and SHUTUP, until you can find the patience to type out a proper explanation of the flaw in another's arguments.
-Adrian

PS: Zim, did you apply your TIM (AS 5?) according to the manufacturers instruction? It would seem unlikely that ALL of the heatpipes leaked. In my case, I used AS Ceramique. I have a buddy who built a machine identical to mine, and his temps are within a degree of mine too.

 

[Zim]

I think I need to work on my airflow. When I take the side of the case off the cpu temp drops by 2C. Also, I still don't understand why the copper base of the Ninja isn't warm to the touch, even after 15 minutes of full load. The Ninja seems to be doing a good dissipating whatever heat it gets, I'm just not sure it's getting a lot of heat.

 

[keldog7]

The base of my Ninja - at least where I can get my fingers into - doesn't feel very warm either, if it means anything.

 

[Zim]

Originally posted by: keldog7
The base of my Ninja - at least where I can get my fingers into - doesn't feel very warm either, if it means anything.

Thanks, that's useful to know. As I said, I think I need to work on my airflow. My case is somewhat jam-packed.

 

[Dave Sz]

Those are horrible temps, just awful. Dude, when your idle temp doubles at load it means you have something really wrong somewhere. Unless your idle temp is is between 10 and 15*c that is.

 

[ianmills]

Have you tried tightening the four screws up on the bottom of the heatsink? the screws I am talking about are the ones that attach the copperplate to the aluminum part of the heatsink.

I was able to tighten each screw about half a turn on my ninja.

I am not sure if it will make much of the difference, but I did that along with a few other things to get a decrease of maybe 9°C at load.