Cooling Low profile cooler test - Noctua L9i vs. ID-cooling IS40 v3 vs. AMD wraith stealth


SFF Guru
Original poster
SFF Time
Jan 2, 2019
Hi guys, I did a small test between listed low profile CPU coolers and wanted to share the results. All coolers are up to 48 mm tall (Wraith stealth with removed shroud).

Tests were done with Ryzen 1500X (65W TDP) on stock settings, on Biostar X370 GTN motherboard. Test was conducted in "semi-open" case conditions (sentry 1.1 without the panel, and without IO shield). Ambient temperature was around 25°C and remained unchanged during the test. I used Arctic MX-4 thermal paste, 1.5mm thick line along the die.
Coolers with heat-pipes were oriented correctly.

Here are the results:

Of course, not all coolers are equally loud, and since I don't have the sound meter, I can only tell my subjective observations.

So, Noctua with retail, slower fan was by far the quietest, but also the warmest. Noctua with it's original, faster fan is good compromise between loudness and cooling, it's not too loud and grabbed the third spot. Also, since it's the shortest, you can put 25 mm fan, but unfortunately I didn't have one, but I want to test that and see the difference.

Wraith stealth with 7 fin was also very warm, and although it was spinning at only 2000 RPM, it produced notable low pitched mechanical hub. I like the 5 fin version more, because it was subjectively quieter and much colder. The secret is probably better motor quality, better fin design, and it has small standoffs below the fan. Interestingly, there wasn't any turbulence with the closed side panel, although this cooler is the highest of all three, and almost touches the panel.

Now, ID-cooling had really nice temperatures, and wasn't too loud, especially with the resistor, and it's not expensive. But, it has two problems. First, it mounts without the back-plate, so it bends the motherboard. That is not a problem per se, but I just don't like the looks of it. Second, it creates most turbulence out of all of the three tested coolers, and that adds to it's loudness when the panel is closed. Also, it would do better with more polished base, and it requires a lot of thermal paste to fill the gaps since it has direct contact heat pipes.

Here is the gallery with all the images: