The Dynatron L31 is a LGA4677 cooler designed for the Intel Xeon Scalable series, codenamed Sapphire Rapids, and its variants. It is not just a standard cooler. Instead, it is a liquid cooler designed to be used in 1U chassis. We have one, so we figured it might be worth showing our readers that may want a solution like this.
Dynatron L31 LGA4677 1U Rackmount Liquid Cooling
The Dynatron L31 is an all-in-one (AIO) cooler design so it is pre-filled with coolant and arrives as one piece.
The cooling block has all of the mounting hardware for the LGA4677 socket. It also has fittings for the tubes built-in. The tubes sit inboard over the center of the cooling block.
Here is a look at the cooling block. It is pre-screened with thermal paste and one can see the copper block is much larger than the LGA4677 CPU.
On the other end, there are a radiator, pump, and fans.
There are three 1U fans that push air through the radiator. These are designed to exhaust hot air through the rest of the server and represent a common design. It provides airflow plus provides cooler inlet temps to help create a bigger temperature differential between the intake side of the radiator and the coolant.
The radiator has a pump with a black power cable. The fans are a different color. One item to remember is that you may need to have a motherboard power input tuned for the pump versus a standard fan for optimal performance.
The radiator has mounting points for fans on the other side as well. For those that are interested, here are the key specs from the company including the power consumption and noise ratings:
Next, we wanted to show the difference between the Dynatron L31 here, for this generation of Intel CPUs, and the Dynatron L32 for the AMD EPYC 9004 Genoa that we also have in the lab.
Dynatron L31 and Dynatron L32 Side by Side
Here is a look at the AMD SP5 socket cooling block for AMD EPYC 9004 series in the Dynatron L32 next to the Dynatron L31 that we have been showing here. This gives some sense of just how much bigger the AMD socket is.
Since these are AIO coolers it is a bit challenging to show them side-by-side. Still, here is a look at the Dynatron L31 for Intel and the L32 for AMD radiators side-by-side.
They are slightly different but very similar designs.
Final Words
The Dynatron L31 is a solution we have used in a pinch with some platforms we are testing and it has worked well. A benefit of the cooler is that it handles 350W TDP CPUs. We do not know if it supports up to 385W for next-gen LGA4677 products, but it at least cools everything we have today. At idle with lower-power Xeon’s using MCC dies, this is actually VERY quiet (<19dBA rating) and could make an interesting companion to rack mounting the Xeon W-2400 series. At 50% duty cycle it is rated at 40.15dBA and at 100% will hit 52.8dBA.
Still, these typically sell for only $119-130, making them in line with Noctua pricing but in a friendlier design for 1U servers. One of the biggest challenges is mounting the radiator in servers. There are often custom chassis holes to mount these solutions. Commonly those types of systems are built for high-frequency trading and other communities, as we saw in our ICC Vega R-116i review. In a pinch, they can also cool a benchtop system with a significantly faster installation time than a tower cooler.
While this is an all-in-one, if you want to see how higher-end liquid cooling in servers works, check out our How Liquid Cooling Servers Works with Gigabyte and CoolIT.
We also were able to check out the CoolIT liquid cooling lab that folks interested in liquid cooling may find fun.
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