First Computer Build, Water Cooling Flow Routing Question

[roketJsquerl]

Have all my parts to build my first gaming computer build, but I have a question about the flow path given to me by Corsair. Using all Corsair parts, including the XC7 cpu, XG7 gpu and XD3 reservoir/pump. Using a front mounted 360 rad/3 LL120 fans and a top mounted 240 rad/2 LL 120 fans. As you can see in the pic, Corsair wants me to flow from the 360 rad to the GPU to the CPU to the top 240 rad then to the reservoir and back to the 360 rad.

 

To limit the crossing of the tubes (I'm going to use hard tubes), and to make it more visually appealing, I would like to route from the 360 rad out to the GPU then to the 240 top rad, out of the 240 rad to the reversed inlet of the CPU (reversed by removing the top cover and inverting the block to put the inlet on the left side), then out of the CPU to the reservoir inlet, then out the reservoir to the 360 rad inlet to complete the flow profile.

 

My only qualm is about putting the outlet of the CPU into the reservoir, and is it recommended to do this. Would this flow cause any temp imbalance or harm the pump/reservoir? I like the idea of having both components cooled by a separate rad, and the use of the 360 rad feeding the RTX 3090 and the increased heat from it.

 

Am I on the right track, or am I barking up the wrong tree?

 

[c-attack]

You can go from CPU directly into the pump/res. The coolant only picks up a few degrees in temperature passing through a cooling block and likewise only drops 1-2C going through a radiator. So regardless of route, you might at worst have a 3-4C difference in coolant temp between the hottest and coldest points of the system. This has no effect on the materials involved and is less than the difference for most people between Winter and Summer room temps. You do need to be more particular about order if you are tying to run mismatched flow directions, like front intake and then top exhaust radiators where one is dumping waste heat into the other. That requires more careful route planning and it is better not to do that all if possible.

[Kuro Houou]

Yeah for me I will have 3x360 rads (O11XL Case).. something has to be an intake, just not enough air if not.. So the bottom is where I plan to have an intake and I will make that one the last rad in the loop before going to the pump.. from what I have measured at the surface level using a temp gun, a typical 360 rad can dissipate about 3C of temperature at load with a CPU AIO. Not sure if that equates to water temp or not, but in my measurements the left side (inlet) is usually about 3 degrees C warmer then the right side (outlet)... So I figure best to take off as much heat as possible before the last radiator as that will be air going back into the CPU and passing through the other 2 rads.

[roketJsquerl]

Thanks for your help guys. I believe I'll keep it with my configuration. Worst that can happen is I'll have to re-route the tubing.

[c-attack]

Yeah for me I will have 3x360 rads (O11XL Case).. something has to be an intake, just not enough air if not..

 

That is a good example of one where flow order will matter. You want the CPU+GPU to go to the top exhaust radiator first ir order to try and preserve some gradual step down in temperature as the coolant progresses down the case. My recommendation is the bottom and side radiators are intake, with the top as exhaust. The problem with the side radiator as exhaust is it gets crippled by the side glass chocking off airflow. With it as intake I can get almost a 2C drop with push-pull on a 54mm thick 360. Flipped around with the same fans the coolant drop does down to 1C and that is with cool air from the bottom. Obviously you can still do the side as exhaust, you just won't get a lot of cooling out of it. That raises the question of whether it is worthwhile to do the triple 360s in the XL at all.

 

The best possible results are all three radiators as exhaust, but in order to achieve that you need to pop off the side glass when under long sustained load. It can't get enough air into the far side of the case for the vertical side radiator and it starves a bit. For most people that's a no-go and one of the other configurations is better.

[LeDoyen]

from what I have measured at the surface level using a temp gun, a typical 360 rad can dissipate about 3C of temperature at load with a CPU AIO.

 

About that, AIOs have a very weak pump compared to what a D5 of DDC can push. That's where your 3° come from. the flow is very slow so there's a big temperature difference.

On custom loop, on a single thin 360 you'll see probably 1° tops.

 

I also do bottom + side intake, and top exhaust, works very well, keeps the case relatively dust free because it stays in positive pressure, and the top rad being the hottest (relatively speaking) it doesn't sacrifice much in terms of efficiency, given how much air the 6 other fans push.

 

Thanks for your help guys. I believe I'll keep it with my configuration. Worst that can happen is I'll have to re-route the tubing.

 

That's what CUSTOM loop is about :) Corsair gave you one possible setup, but you do as you desire.

[Kuro Houou]

Yeah for me I will have 3x360 rads (O11XL Case).. something has to be an intake, just not enough air if not.. So the bottom is where I plan to have an intake and I will make that one the last rad in the loop before going to the pump.. from what I have measured at the surface level using a temp gun, a typical 360 rad can dissipate about 3C of temperature at load with a CPU AIO. Not sure if that equates to water temp or not, but in my measurements the left side (inlet) is usually about 3 degrees C warmer then the right side (outlet)... So I figure best to take off as much heat as possible before the last radiator as that will be air going back into the CPU and passing through the other 2 rads.

 

 

I have a O11XL as well.. just finished my build. I had the bottom as an intake and the last rad in the loop, but it still was blowing in 90+ degree air.. That is not good! That means the other two rads are having to try and cool liquid starting with 90 degree ambient temps!!

 

That said, I reversed my bottom fans and now all three are exhaust. No issues sucking in air imo. I also made some custom air filters for the rear to limit dust intake. Pushing over 600 Watts TDP in my system now and water temps stay about 36-38C.

 

That said, open to seeing more data on different configs.. I might play around with them some more honestly.. who knows maybe there is something better. Other benefit is, all your other system components stay super cool as no hot air gets in.. i.e. chipset/vrms/m.2's all very cool.

Edited January 19, 2021 by Kuro Houou