Liquid Cooling for Ryzen 1700 OC

Sep 11, 2018
Hi, my question in nutshell is, that how much of a difference does 240mm rad makes compared to 120mm one. I'm planning some overclocking on my ryzen 1700 and want to ditch the stock cooler. I have a CM Q300L case with 2 140mm fans installed on the front of it. So if i buy 240mm rad i have to sacrifice them. So am I going to be okay with CM ML120l RGB or should I really go for the ML240l RGB and my 140 fans doesnt really matter.

Edit: Also my GPU is a GTX 970 G1 and if not sure if it will fit with the 240 on the front. So really am i missing out on much with a 120mm AIO?


Oct 8, 2012
A single fan and a 120mm rad would be fine. Push pull fans won't do much to temps and a bigger rad will only help 'capacity' aka the speed that your CPU raises to max temp under load... it won't be much cooler without two adjacent fans. The fans are still what is ultimately cooling your setup, because water isn't very good at dissipation.


Contributing Writer
To offer a bit of debate:

240 radiator over a 120 makes a rather considerable difference, actually, but ultimately comes down to thermal load at peak usage.

Push pull also does improve cooling - radiators and heatsinks cause dissipation and resistance that 1 fan often struggles to force air through. If you have enough depth, this is the ideal fan setup for almost every radiator, however normally chassis space is limited, so only 1 set of fans is typically used, also because this is the cheapest solution.

The fans are still what is ultimately cooling your setup, because water isn't very good at dissipation.
Correct, which is why a 240 radiator is often beneficial over a 120, especially over 150w TDP (overclocked or not). Liquids such as water and water-based coolants, like glycol mixes typically used in AIO coolers, are able to absorb significant volumes of thermal loads before the actual CPU begins to see temperature increases. Likewise, this is also the same reason that liquid cooling radiators often remain warm for several minutes after load ceases. If you do not have enough liquid volume to absorb the entirety of the thermal load while also being able to dissipate a relatively equal delta of thermal volume simultaneously, the cooler theoretically will continue to absorb more and more heat, getting warmer and warmer.

Think of a boat - almost every boat leaks or takes on some water but also has pumps to discharge it back into the ocean or lake. If the boat takes on more water than it can pump out...well, you get the idea.