Conclusion
One of the most revered SSD coolers ever. With the CLR-M2XT, Axagon opted for a transverse fin layout, which makes this cooler different from all the others (within Axagon). The fins are naturally shorter and there is less surface area per one, but again there are more of them and to achieve the highest cooling performance the designers tried to work well with the height as well. But, again, in a way to maintain as much compatibility as possible.
Conclusion
Axagon CLR-M2XT is characterized by above-average cooling performance among passive SSD coolers. If you don’t have a cooler above one of the M.2 slots, or if you do but it is a weaker performing cooler, the CLR-M2XT will be a good fit.
It’s especially useful in places where a taller cooler (such as the Axagon CLR-M2XL) won’t fit due to collision with the CPU cooler fins.
Despite the above, it should be noted that comparable cooling performance is also achieved by significantly lower or significantly cheaper Axagon coolers. From the lower ones it’s the CLR-M2 model, from the cheaper ones it’s the CLR-M2L10 model. With these coolers, we even noticed a one degree Celsius lower controller temperature, but again the CLR-M2XT cools the memory of the tested SSD by 3–4 °C better. Given the significantly higher weight than several coolers with very similar cooling performance (including the BeQuiet! MC1 Pro or Gelid IceCap), this raises the question of the effectiveness of the transverse finning.
Other transversely finned coolers such as the Akasa Gecko Pro or Thermalright HR-10 2280 often lag behind competing longitudinally finned models or achieve similar results even when using more material with a larger overall emissive surface area. Of course, then there’s one more thing, and that’s the orientation of the fins relative to the airflow of system cooling (from bottom to top instead of the usual front to back scheme).
It is possible and likely that the CLR-M2XT would perform slightly better after a 90-degree rotation, but we don’t anticipate that these will be major differences that would flip the ranking vs. coolers with longitudinal finning. We will look into this issue in the future anyway and test this Axagon cooler later on a motherboard that has a longitudinally oriented M.2 slot, but there are quite few such motherboards, and when you do come across one, it often has its own SSD cooler, and even one that is more effective than average, whether it’s the situation on the ASRock B650E Taichi or the MSI MEG X670E Ace.
The effectiveness of the Axagon CLR-M2XT cooler will also depend on the airflow of the system cooling more than other models. This is due to smaller fin spacing with the need for higher pressure. Thus, as the airflow increases, the relative advantage of this cooler over others with typically thinner fins could increase even further. Transversely finned coolers could have the upper hand in fanless systems, where the cooling of the heatsink depends on the natural upward rise of warm air.
The relatively poorer performance of transversely finned coolers may also be related to more microturbulence, as they have more fins and sharp edges, which are points of lower pressure/airflow through the cooler, and thus less heat is dissipated from the heatsink. But this is already so much speculation, hypothesizing, that it almost seems like the CLR-M2XT might not be a good cooler after all. It certainly is, but when confronted with seventy other models it, of course, does not have it easy.
Finally, with the CLR-M2XT, it is also worth highlighting the reliable mounting with the backplate. Axagon has made an improvement to it, between generations, with the backstop that makes installation more user-friendly than with older models. And then the backplate is also useful in that it prevents the SSD from bending in cases where for some reason the PCB of the motherboard is being warped.
Overall, the Axagon CLR-M2XT can be recommended (and reward it with „Approved“). It will handle all current SSDs, including the most powerful PCI Express 5.0-enabled models, and will perform at all times, even in cases with weaker air circulation from system fans.
English translation and edit by Jozef Dudáš
| Axagon CLR-M2XT |
| + Peak cooling performance. Significantly reduces SSD temperatures |
| + Robust build. Thanks to the backplate, the SSD never bends |
| + Spare components (thermal pad and extra screws) |
| + Useful technical details beyond competitive solutions |
| - Compared to the most powerful motherboard solutions, still lower TDP |
| - Won't fit in the slot behind a graphics card. The cooler is too tall for that |
| Approximate retail price: 14 EUR |
I am using what appears to be the same cooler but with a different name (Jeyi Godfins) in my build, the decision based on tests by BuildOrBuy on YouTube: https://www.youtube.com/watch?v=v5Mc3SGW3e4
In his tests, the results appear to heavily vary between the two orientations he tested. Lying flat, it’s 52C, while rotated by 90 degrees it results in 44C (for reference, the Jeyi iGlacier8, which seems identical to the Axagon M2XL, is 48C no matter what orientation it is in).
Note that the Axagon and Jeyi variants come with different thermal pads. Mine comes with little square pads with different thicknesses, which I careful choose and tested ones that can even out the surface (for example, the DRAM chip is lower so I used slightly thicker pads). The holes on the base allow me to shine a light through and verify that contact is perfect between the heatsink, the pads and the SSD. It’s curious that Axagon chose long pads instead (which I assume are the same as the ones on the M2XL).
This surprises me, since in both cases there is a vertical orientation of the fins. With such a reorientation of the heatsink, where in one case the fins are horizontal and in the other vertical, under certain circumstances, for example in system cooling without fans, the heat will be dissipated from the heatsink faster in the second case (vertical orientation of the fins) compared to when the fins are horizontal to gravity and more heat accumulates under each one.
Assessing the efficiency of passive coolers is extremely complex. When combining different positions with different airflow intensities, we would probably find that the variance in cooling performance can be quite wide. And in different situations there will be different orders of magnitude. The components that are around the cooler then also have an effect on the cooling. The (non-)presence of an expansion card can affect the airflow around the cooler quite significantly. Taking all of this into account, it will certainly drive you crazy and probably unnecessarily so, because very few people will be interested in such analyses. 🙂
In my fully passive system (Noctua NH-P1 w/ i5-11400, Palit GTX 1650 Kalm X, Seasonic Prime Fanless PX450), I have replaced the Axagon CLR-M2XL coolers on my 2 TB Kingston KC2500 and KC3000 drives with these M2XT coolers and both drives no longer hit 70dC under 15 min continuous load at 28dC ambient in a full system stress test scenario. Not a big surprise though, vertical orientation of fins is always better for natural convection.
Yes, for passive builds (i.e. without system fans), a vertical orientation of the fins is beneficial for achieving the highest possible cooling performance.