Cooler Master ML360 Sub-Zero Review: Frigid Temps for LGA1200

Sub-ambient liquid cooling…How low can you go?

Cooler Master ML360 Sub-Zero
(Image: © Tom's Hardware)

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For our CPU cooling tests, we use the same hardware, overclock and configuration for each test to minimize environment variables. This allows for results across all coolers tested on the platform to be viable as side-by-side examination for direct compare/contrast. Here’s a list of the components in our testing rig. 

Swipe to scroll horizontally
CPUIntel i9-10850K LGA1200 (Comet Lake), all 10 cores  4.6Ghz @ 1.190v
Row 1 - Cell 0 (3.60Ghz stock speed, single core boost @ 5.2Ghz)
MotherboardMSI Z490 MEG Godlike (bios vers. 7C70v12)
MemoryCorsair Dominator Platinum RGB, 16GB (2x8GB) DDR4-3600
StorageCorsair MP600 m.2 2280 NVMe, 500GB
GraphicsGigabyte GTX 1050Ti
Power Supplybe quiet! Dark Power Pro11 1200w
ChassisCorsair Graphite 760T
MonitoringCrystalFontz CFA-633-TMI-KU, 4x Dallas One Wire WR-DOW-Y17 sensors
Fan ControlCorsair Commander Pro, 100%/50% PWM Speed profiles (liquid cooling pump always @100%, if applicable)
OSWindows 10 Pro 64bit
Networking Disconnected, not used
Thermal CompoundArctic MX-4

Data comparisons are based on data collected from testing performed on our Intel i9-10850K system, including re-visiting many previously covered products which were originally covered on the prior testing platform which was based around an i7-5930k (4.20ghz @1.20v).  

Prime95 v29.4b8 (no AVX) is used for two-hour intervals, one managing fans at 50% PWM and the other at 100% PWM, with RPM measurements being taken every 3 seconds and averaged across the duration of each 2-hour capture. Omitting AVX instruction sets allows for accurate, 100% loads at chosen clock speeds. Allowing AVX instructions would provide higher, albeit unrealistic, synthetic CPU loads and excessive heat production, less indicative of real-world use.  

This also allows for a greater range CPU coolers to be tested and compared without the need to configure the system differently for smaller coolers which may not handle the excessive thermal loads being generated during testing, while larger coolers might be better equipped to manage heat output produced by the i9-10850K.  

While the test platform is quite capable of a 10-core overclock at 5.0Ghz and 1.265v, we were seeing 360mm AIOs struggle to keep core temperatures in check at lower fan speeds, providing insight that the enthusiast-grade i9’s need excellent cooling if the goal is overclocking.

HWInfo64 is used for real-time core temperature readout, thermal throttling alerts, motherboard power consumption, CPU speed and logging of data, while a CrystalFontz CFA-633-TMI-KU is used to monitor and later average both ambient room (2 probes) and motherboard voltage regulator heatsink (2 probes).

Garrett Carver
CPU Cooling Reviewer

Garrett Carver is a contributor for Tom’s Hardware, primarily covering thermal compound comparisons and CPU cooling reviews; both air and liquid, including multiple variations of each.

  • Friesiansam
    Noisy, inefficient, can't cope with OCing and very expensive. Hard to see the point of buying this.
    Reply
  • Rakanyshu
    Friesiansam said:
    Noisy, inefficient, can't cope with OCing and very expensive. Hard to see the point of buying this.
    does it have RGB? if it has there you have a huge market for it.
    Reply
  • gargoylenest
    I believe the technology would be much more efficient if used perpendicular between the fans and the radiator to push cold air in the radiator fins without direct heating on the Peltier plates.
    Reply
  • rubix_1011
    The overall question of performance is the most notable here, but the bigger conversation is around how to integrate and improve upon this with future solutions. Like anything else, it lends an exciting look into some new approaches to cooling technologies to see how well it is adopted by the public.

    Yes, we look at this product 'now' but the more curious questions lie in 'what is coming next as a result'?
    Reply
  • deesider
    rubix_1011 said:
    The overall question of performance is the most notable here, but the bigger conversation is around how to integrate and improve upon this with future solutions. Like anything else, it lends an exciting look into some new approaches to cooling technologies to see how well it is adopted by the public.

    Yes, we look at this product 'now' but the more curious questions lie in 'what is coming next as a result'?
    In this case the very concept is patently absurd.

    Peltier cooling is extremely inefficient and that isn't going to change any time soon. The end result of using a Peltier cooling in an enclosed case is simply to add 100W of heat into the case while cooling the processor by about 10W. It could be improved of course by placing the Peltier device outside the case so that it would take heat out of the coolant as it passes though, but still only by 10W. Which is rather insignificant given the trouble of an external cooling device.

    Since it can only cool the CPU below ambient when the CPU is at idle, it has no purpose other than a gimmick. Although it is possible to connect a Peltier cooler large enough to match the heat output of the CPU, the cooler itself would consume so much power there wouldn't be any left for the PC.

    - In other words, no one should ever buy this.
    Reply
  • escksu
    rubix_1011 said:
    The overall question of performance is the most notable here, but the bigger conversation is around how to integrate and improve upon this with future solutions. Like anything else, it lends an exciting look into some new approaches to cooling technologies to see how well it is adopted by the public.

    Yes, we look at this product 'now' but the more curious questions lie in 'what is coming next as a result'?

    Peltier coolers are nothing new. They were around during Pentium days as well. Unfortunately, they face exactly the same problem as this cooler master kit. So, after a while, it died and nobody bothers about it.

    Now, companies are trying to recreate something that failed and couldn't work....

    Peltiers don't work, period. Iaws of physics that cannot be changed, regardless of the approach. Peltier is a heat pump, not a cooler. IF you have a CPU generating 200W and your peltier is rated 200W, you get 0C difference between cold and hot side. However, you are dissipating 400W.... Might as well not use the peltier.

    With overclocked multicore CPUs hitting over 200-300W, you need 300-400W. Then you are dissipating 500-700W. Even a triple 12cm rad may not be sufficient. IF you have 10-16 core ones, its even worse.
    Reply
  • Co BIY
    Might be more practical to buy a window AC unit and blow it directly into your case.
    Reply
  • watzupken
    So running an Intel CPU with up to 250W of power and a graphic card drawing 200 to 350W of power is not enough. Coolermaster wants the cooler to also draw 200W? If they want to do that, at least make it cool the CPU effectively. The 360 AIO is now doing double duty of cooling the CPU and Peltier now. I guess one may get better results by just buying a cheap 240 AIO to cool just the CPU and save at least 90% of power on cooling.
    Reply
  • tresnugget
    So toms hardware completely missed the point of this cooler. It's not for single core/thread overclocking. It's for creating custom TVB rules to get insanely high frequency at low thread counts, pretty high frequency at medium high thread count, and slightly overclocked frequency at full thread count. You really need a decent binned CPU so using a 10850K isn't really advisable.
    Reply
  • PapaCrazy
    escksu said:
    Peltier coolers are nothing new. They were around during Pentium days as well. Unfortunately, they face exactly the same problem as this cooler master kit. So, after a while, it died and nobody bothers about it.

    Now, companies are trying to recreate something that failed and couldn't work....

    Peltiers don't work, period. Iaws of physics that cannot be changed, regardless of the approach. Peltier is a heat pump, not a cooler. IF you have a CPU generating 200W and your peltier is rated 200W, you get 0C difference between cold and hot side. However, you are dissipating 400W.... Might as well not use the peltier.

    With overclocked multicore CPUs hitting over 200-300W, you need 300-400W. Then you are dissipating 500-700W. Even a triple 12cm rad may not be sufficient. IF you have 10-16 core ones, its even worse.

    Exactly. Nobody can beat the law of conservation of energy. The energy is transferred to the PSU, which is now forced to do the cooling on top of powering everything else. The only solution would be an external PSU, but personally I wouldn't bother with a PITA setup like that.
    Reply