Noctua NH-L12-Very quiet, but not as effective as expected

[Dale F]

I bought the Noctua NH-L12 CPU cooler. The SPCR article showed this CPU cooler allowing an AMD 95W CPU to rise by only 14 to 22 degrees Celsius, depending on fan speed. See http://www.silentpcreview.com/article1261-page6.html.

My CPU is an Intel i7-3770S 65W CPU rather than the AMD 95W CPU used in the article, so I had expected that the worst temperatures I would see would be about 45 degrees (22 rise plus 23 ambient).
My actual results, with Prime95 for full CPU load and with both CPU cooler fans at 100% are 61 to 63 degrees, or a rise of 38 to 40 degrees. So twice as much of a CPU temp rise as I expected.

I am unsure if I should be concerned about the high temperatures I am seeing, and if this is the best the CPU cooler can do, so I asked Noctua support the following questions: Should I ask the retailer to re-install the CPU cooler? Perhaps they forgot to apply the thermal paste (TIM), or the CPU cooler is not seated correctly? Or is 63 degrees within the general range that you would expect?
The answer from support is:
>
62degrees are fine for your CPU under full load, because unfortunately Intel has decided to stop soldering the die of the CPU to the heatspreader which increased temperatures compared to previous generation CPUs. [...] In my opinion there is no need for action and I would recommend you to leave the CPU cooler alone.
[...] it is fairly normal that AMD temperature-readings are different from Intel readings, because Intel CPU temperatures are measured at the core of the CPU while AMD CPUs report Tcase (=temperature at the heatspreader) values.
<



To prevent any confusion, I am not saying the Noctua NH-L12 is bad. I am VERY impressed with the noise levels. At 40% PWM duty, I cannot hear the fans at all, even with side of the case open. My idle temps are 26-27, or 3-4 degree rise.
At 100% PWM, when the CPU is under full load, I can hear the fans, but it is not that bad. I can definitely tolerate that fairly low level for the times when the CPU will be at 100%, which I anticipate to be infrequent.
When I test the CPU temperature 20 seconds after stopping Prime95, the temperatures have already dropped to 29 or 31 degrees, or 6-8 degrees above ambient.

Any comments on the temperature of 63 degrees (40 degree rise) at full load? Is this safe? Is this what you would expect from a good CPU cooler?

Mod: moved to CPU cooling forum.

[faugusztin]

What you are seeing is very likely the TIM IHS issue as mentoined in the answer from Noctua. Some people cut the IHS, replaced the TIM with different stuff and put the IHS back and they got 10-15C improvement at load. 60-65C is fine, Intel CPU has a 100C max temperature (and that throttle/shutdowntemperature is not even the core temperature).

[MikeC]

22c sounds like the room temp. You need to consider the air temp inside the case, next to the cpu, as the starting ambient temp. Agreed that your temps are perfectly good.

[Scrooge]

You also need to be aware that while your IVB CPU has a lower TDP than the AMD one in the SPCR review, it has a higher heat density because the die is very small. This means the heatsink has less area to pull heat from, and the energy that remains raises the die temperature higher than the larger AMD die.

A few years ago, giant tower coolers were getting the larger die, slower CPUs of the day to mid-40s *C under synthetic load. While that's great, I think some people lost sight of the fact that 60-something *C is hardly "bad"; that leaves plenty of overhead before throttling. I do, mind you, wish Intel hadn't cheapened out on the TIM; hopefully HSW won't have that issue.

[Dale F]

Thanks for all the input guys; appreciated.

Now to go enjoy my new computer... It is SO nice to not have to hear the computer.

[Cod]

I'm running the NH-L12 on my i5 3570K @ 4.2GHz. My max temps are around 70C after an hour or so of gaming and in the 76-77C range when running IBT. If I downclock to stock, temps never get about 64C under load and 67C under Prime95.

I reinstalled the NH-L12 multiple times before being happy. I think I tried all four orientations available. I have a horizontal case (GD05), so not limited to only three orientations. Do you know which TIM your retailer used? I hope they used the NH-T1 that came with the cooler, but they may have used a less effective TIM.

With all that said, I wouldn't worry too much. Like others stated, your temps are perfectly fine.