Optimal Fan Configuration For 5000X and High end GPU/CPU

[CowMcMoo]

Hello, I'm doing my first build in 9 years so decided to go all out, I've already purchased an H150i ELITE CAPELLIX XT and 6 AF120 RGB Elites which combined with the AIO and the case (5000X QL Edition), I have 13 fans total (9 AF120 RGB Elites, and 4 QL120s from the case). I plan on getting an AMD 9 9950X3D and RTX 5090 when they both come out early next year so my PC will run fairly hot. I'll be doing push/pull AIO but can't decide if top mount exhaust or side mount intake would be better for temps. Anyone have experience with a high end GPU that's tried both and have opinions to share on temps? The way I understand it:

1. Top mount exhaust will run hot air from the GPU through the rad causing much higher CPU temps when running both under load (especially true if using an air cooled GPU), but cooler air from the 6 side/front intake fans.

2. Side mount intake will push fresh cold air through the rad causing better temps for the CPU but warmer intake air across the system. Normally the delta for internal case temps shouldn't be that much of a difference especially with 3 front intakes as well, but with the 5090 running much hotter than other cards, does this affect the decision making?

Any other configurations that would make sense? Also if I do front/side mount, the tubes should go on bottom correct (first time building with AIO)? Thanks for the help in advance!

Edited November 25 by CowMcMoo

[c-attack]

Side mount for the CPU AIO will be better regardless of whether you do it as intake or exhaust.  In water cooling you scrap for -1C here and there with fan upgrades, a higher flow rate, doubly expensive CPU block, push-pull on the fans all only offer a tiny improvement.  This is dwarfed in comparison to what happens when you blow 600W through the CPU radiator up top from the huge air cooled GPU below.  If you put 45C air through the top radiator, you coolant temp and CPU now have a 45C minimum temp at 0W.  People have been putting AIOs up top for a long time, but for the most part because the only other option was to front mount and really restrict airflow into the case.  There were negative consequences to both placements.  Now that all these cases have the motherboard wall side mount this becomes a better choice for most people.  Without the radiator there, those three fans don't add too much in terms of direct airflow cooling (wrong angle) and you don't need a lot of exhaust in the front of the case.  On the other hand, it's great for the CPU radiator guaranteeing it has cooler intake air if used as exhaust or near direct intake air if pulling in from the back.  One caveat on this.... if you are going to keep the back of your case close to wall, run the radiator as exhaust to the back.  During longer load sessions you will heat of the air surrounding the case unless something else is influencing things, the air between the case and the wall isn't going to be all that cool.  

People have really become obsessed over this tubes up/down thing lately.  It has never mattered much and only becomes a solvable problem in some niche instances.  You should do it in the way that makes sense for your build and how you can route the tubes.  If you have to lay the tubes across the GPU in order to get to the bottom of that side panel, that's a bad trade and melted sleeving is certainly worse than running the tubes to the top.  The one thing you don't want is the CPU block as the highest point.  That only happens when you try to put the radiator on the bottom of the case.  Not going to be an issue here.   

I do see one obstacle with the current list of gear.  Corsair gear from that generation is limited to 6 fans per controller (RGB or PWM speed control).  Commander Core (Elite Capellix) and Commander XT controllers can handle mixed LEDs counts, so QL and AF-Elite on the same controller is OK.  However, you are going to be one fan over at 13.  Technically this means you need 3 controllers.  Should be a Lighting Node Core in the box with the case and that is RGB controller #3.  It won't have speed control, but you can get away with using a simple two way PWM splitter to pair a set of QL or AF fans somewhere.  However, if you are going to do push pull you might consider using a powered PWM hub instead and that will solve a few problems.  A PWM hub is a powered splitter.  It's usually in circuit board form (may or may not be covered) with a SATA connector for power.  That takes it's fan load off the commanding controller.  A control lead goes from the PWM hub to one of the Commanders and makes all fans on the hub run the same speed -- just like a splitter.  The place to use this is on the 6 AF-Elites in push-pull on the radiator.  That takes 6 fans off your fan controller load and free up space for a lot of other possible arrangements.  It also lets you set the entire radiator array with one click in the software.  Having to set each fan individually on big radiators is annoying and unnecessary.  They always will run the same speed and you don't need per fan control.  

Also keep in mind that each RGB controller is a separate, self-contained lighting group.  You can't make lighting waves jump from controller to controller around the case.  They will run their pattern on the fans, on that controller only.  So keep this is in mind when setting up your groups.  You do want the radiator fans on the Commander Core (or at least the PWM hub) so it can use coolant temp direct from the pump when when CUE is not running.  Aside from that, you are effectively creating lighting zones with the 3 controllers.  

[CowMcMoo]

2 hours ago, c-attack said:

Side mount for the CPU AIO will be better regardless of whether you do it as intake or exhaust.  In water cooling you scrap for -1C here and there with fan upgrades, a higher flow rate, doubly expensive CPU block, push-pull on the fans all only offer a tiny improvement.  This is dwarfed in comparison to what happens when you blow 600W through the CPU radiator up top from the huge air cooled GPU below.  If you put 45C air through the top radiator, you coolant temp and CPU now have a 45C minimum temp at 0W.  People have been putting AIOs up top for a long time, but for the most part because the only other option was to front mount and really restrict airflow into the case.  There were negative consequences to both placements.  Now that all these cases have the motherboard wall side mount this becomes a better choice for most people.  Without the radiator there, those three fans don't add too much in terms of direct airflow cooling (wrong angle) and you don't need a lot of exhaust in the front of the case.  On the other hand, it's great for the CPU radiator guaranteeing it has cooler intake air if used as exhaust or near direct intake air if pulling in from the back.  One caveat on this.... if you are going to keep the back of your case close to wall, run the radiator as exhaust to the back.  During longer load sessions you will heat of the air surrounding the case unless something else is influencing things, the air between the case and the wall isn't going to be all that cool.  

People have really become obsessed over this tubes up/down thing lately.  It has never mattered much and only becomes a solvable problem in some niche instances.  You should do it in the way that makes sense for your build and how you can route the tubes.  If you have to lay the tubes across the GPU in order to get to the bottom of that side panel, that's a bad trade and melted sleeving is certainly worse than running the tubes to the top.  The one thing you don't want is the CPU block as the highest point.  That only happens when you try to put the radiator on the bottom of the case.  Not going to be an issue here.   

I do see one obstacle with the current list of gear.  Corsair gear from that generation is limited to 6 fans per controller (RGB or PWM speed control).  Commander Core (Elite Capellix) and Commander XT controllers can handle mixed LEDs counts, so QL and AF-Elite on the same controller is OK.  However, you are going to be one fan over at 13.  Technically this means you need 3 controllers.  Should be a Lighting Node Core in the box with the case and that is RGB controller #3.  It won't have speed control, but you can get away with using a simple two way PWM splitter to pair a set of QL or AF fans somewhere.  However, if you are going to do push pull you might consider using a powered PWM hub instead and that will solve a few problems.  A PWM hub is a powered splitter.  It's usually in circuit board form (may or may not be covered) with a SATA connector for power.  That takes it's fan load off the commanding controller.  A control lead goes from the PWM hub to one of the Commanders and makes all fans on the hub run the same speed -- just like a splitter.  The place to use this is on the 6 AF-Elites in push-pull on the radiator.  That takes 6 fans off your fan controller load and free up space for a lot of other possible arrangements.  It also lets you set the entire radiator array with one click in the software.  Having to set each fan individually on big radiators is annoying and unnecessary.  They always will run the same speed and you don't need per fan control.  

Also keep in mind that each RGB controller is a separate, self-contained lighting group.  You can't make lighting waves jump from controller to controller around the case.  They will run their pattern on the fans, on that controller only.  So keep this is in mind when setting up your groups.  You do want the radiator fans on the Commander Core (or at least the PWM hub) so it can use coolant temp direct from the pump when when CUE is not running.  Aside from that, you are effectively creating lighting zones with the 3 controllers.  

Thanks for the response! I actually did get the the 3 packs for the AF120s so I have a couple lighting nodes. I also bought a separate powered PWM hub and internal USB 2.0 hub so I should be good on connections I believe.

I have about 8 inches of clearance from the side fans to the wall so I think I should be ok to do intake. I will go with side mount push-pull intake, 3 front intake, 3 top exhaust, and 1 rear exhaust then!

[c-attack]

If you can't quite fit the push-pull on the side wall, it will be OK.  We don't know the exact peak sustained power draw on the 9950X3D yet, but generally the difference between a single layer of 120 fans on a 30mm, medium FPI radiator is about 1-1.5C at 300W and 1300 RPM fans.  We know the 9950X3D will not be pulling 300W and a steady 150W power draw is more likely, having the difference.  Where the push-pull has more value is if you intend to keep the fans at lower speeds even when under load. In the 700-1100 rpm zone there is more temperature difference in play and you can pull back a couple of degrees for moderate loads like gaming.  Also, sometimes this is  not a good physical fit.  If the inside the rear panel group of fans are too close the rear panel, you may get more noise out of it than is worthwhile.  The 5000X has a mesh cutout back there to help with that, but this is still going to be user specific.  

[CowMcMoo]

The more I play around with it the more it seems unlikely I'll be able to fit a push-pull on the side wall 😞 From your above comment I presume you're suggesting to just go with a 10 fan setup side mount intake and return one of the 3-packs? It's unfortunate since the 5000X looks like it has such a convenient top mount push-pull design, but not one for side mount. It would also mean I could return my PWM repeater and just use the one in the case with the Commander Core since i no longer have 1 extra fan that needs a separate hub.

[c-attack]

We probably need a 5000 owner to comment on the space limitations and if there is a work around.  I don't want to say without the case on hand.  However, as mentioned push pull is worth a about 1-1.5C at medium fan speed with a large power load.  We know for sure the X3D version of the 16 core is not going to be a 300W draw or anywhere close.  The best part of the X3D power efficiency is you don't need to worry about cooling.  Going single sided fans is not going to have any performance impact for your proposed setup.  On the other hand, most users typically see the coolant temp go +10C when gaming when the AIO is mounted in the top as exhaust.  Almost all of that is GPU waste heat and the environment is also +8-10C.  There is very little you can do about that and it is a guaranteed +10C penalty to CPU temp.  

[CowMcMoo]

So after some Black Friday deal hunting I actually ended up redoing a couple things. There was a Newegg bundle for the 9800X3D + iCUE LINK H150i RGB which comes with 3 QX120 fans. I decided to return the Capellix XT since the Link AIO was only $20 more and lets me start to transition into the iCUE Link ecosystem which seems a lot more preferrable. After the discussion above it was already apparent that I didn't need one of the 3 packs of fans. Now that I'm switching over to the iCUE Link setup, I'll probably return both sets of AF120 RGB Elites and for the same price of 6 AF120s just get either 3 RX120s or 2 RX140s. So would the new ideal setup look something like:

1. 1 QL120 (that came with case) as rear exhaust

2. 3 QL120s (that came with case) as top exhaust

3. 3 QX120s (that came with the AIO) on the side mount rad as intake

4. 3 RX120s OR 2 RX140s as front intake

Or is there a better configuration for which side the QL/QX/RX fans should go on (like QL front, QX top, RX rad, etc)

Unfortunately, because the case still comes with 4 QL120s, I have to mix and match the older fans with the newer Link fans, but over time I'll probably be able to replace these and eventually fully upgrade to iCUE Link fans. From what I understand, the QX and RX fans are better than the AF fans anyways for airflow, noise, and temps. Rather than buying a separate Commander Core XT just to control the QL120s from iCUE, I think I'm fine with just plugging the PWM repeater into the mobo fan header and controlling the top and rear exhaust QL120s from the mobo. The RGB for them would go with the lighting node included in the case. Then everything else that's part of iCUE Link should be able to connect to the Link hub dramatically simplifying the rest of the cable management. Couple questions here:

1. For front intake, would 3 RX120s or 2 RX140s be better? I get that 2 140mm fans will be quieter even though 3 120mm fans move more air, but from what I understand, the bottom 120mm fan is somewhat pointless anyways since it's just blowing air into the PSU shroud. It probably looks slightly worse symmetrically having 3 120mm fans on the sidemount rad and then only 2 140mm fans on the adjacent front intake, but I don't really mind if the performance is more optimal.

2. Regarding connections, just to make sure I have everything covered on this new system I'll need 1x lighting node and 1x PWM repeater (both included in the case) for the 4 QL120s, the PWM repeater now connects to a fan header on the mobo since no more Commander Core and the lighting node still connects to a USB 2.0 header for iCUE RGB control. Both require SATA power. With the Link components, the RX/QX fans and the AIO should be able to all connect together either directly or via bridge and then the entire grouping can of them can go into one active port on the Link Hub? From what I understand each of the two active ports can support up to 7 fans so the AIO+3 fans+2 or 3 intake fans should be sufficient for one port allowing for future expansion on the other side if needed. The Link Hub will require PCIE power and a USB 2.0 header as well as the tach cable for CPU_FAN. In total for connections it will be 2 USB 2.0 headers, 1 CPU_FAN header, 1 system fan header, 2 SATA power and 1 PCIE power? Or am I missing anything?

 

 

Edited November 28 by CowMcMoo

[c-attack]

9 hours ago, CowMcMoo said:

I decided to return the Capellix XT since the Link AIO was only $20 more and lets me start to transition into the iCUE Link ecosystem

I agree with this. 

 

You're getting 3 QXs with the AIO.  Despite what the Reddit crowd offers as advice, the actual difference in airflow between a QX, LX, and RX is somewhat minimal until you create a "worst possible circumstance" kind of situation.  If you could change your fans on the radiator and drop 5C, everyone would do it and the other fans would cease to exist.  I can't tell you how difficult it is to pull back 5C in water cooling with fan changes, block changes, pump speed, etc.  You typically only see changes like this when you push something to the far end of the spectrum --- ultra low fan speed (400 rpm), pump speed too low, super dense 60mm thick radiator, front intake radiator with a dust filter and tight fitting glass front panel.  We are still waiting for more in depth professional reviews on the LX fan, but it's going to be very close to the RX with a slight (fraction of 1 cfm) advantage at lower speeds and the RX will have a fractionally higher throughput at moderate speeds.  Below is a comparison chart of a number of fans.  RX and QX are in there.  It follows logical lines.  Fans that move a little less air, also make less noise. Fans that move a ton of air, will make more noise.  It's rare you get a fan that can be in the higher airflow side of the chart, but also in the lower noise half of the chart. 

https://www.techpowerup.com/review/corsair-icue-link-rx120-rgb-120-mm-fan/5.html

 

Airflow through a radiator and actual temperature reduction from it do not have a linear relationship.  So with any particular fan x 3 on a 360mm radiator with a heavy 300W load, we would expect to see about +15C coolant at 750, +9C at1300 rpm, and plus 6C at 1800 rpm.  Lower fan speeds struggle to overcome the resistance of the radiator, but once you get air moving through the fins it doesn't keep scaling up for temperature reduction.  There are different properties between radiator designs and you can make a radiator that does really well at high speed but very poorly at low speed and vice versa.  Corsair AIO radiators are going to be designed for low to moderate speed effectiveness.  Nobody in this segments wants an AIO that chokes because you run the fans quietly on the desktop and very few of us can stomach 1800-2400 fan speeds.  So when you see a 2 cfm difference in airflow (x 3 fans) for 6 cfm at moderate speed, you're really looking at only a 1C difference in actual temperature reduction.  That is an irrelevant difference until you start stacking more things against the fan.

As such, what I tell most people is pick the fan you really like.  These are too expensive to choose one you don't really like for some elusive temperature change, unless that is the one thing that matters to above all else.  If you fill the case with QX fans, you likely will never see a performance deficit.  The solution to make up your missing 6 cfm is run each fan 50 rpm faster.  Now they are even.  Caution on the RX model. There is a large light up side section that is clearly visible in most mounting installations.  Take a look at some pictures around the internet before buying.  I think they are harder to match with other fans.  Either all RX or go a different direction.  However, the LX does has similar properties to the RX for performance but looks a lot more like the QX, especially from the front.  Where those two fans look different is the vanes in the back, something that will only come into play if you run the radiator as intake on the side.  You can choose whether you want LX or QX there and spread the others around.  Both LX and RX are ring fans and will have similar effects.  RX fans are 8 LED center hub models and won't do all those cool ring effects.  I think you check out the deals around this week.  As the "older" model from last year, there may be sales on the QX.  RX and LX are newer and may not receive discounts, but I do think you should choose between more QX or mixing with LX.  

Edited November 28 by c-attack

[c-attack]

I have a much longer post explaining the reasons that is currently held up, but if you are shopping today make sure you look at QX or LX.  The LX will be a better aesthetic fit with the QX compared to the RX and its very different LED geometry.  There is no meaningful performance difference between a LX and a RX.  The difference between either RX/LX and QX is minimal to undetectable in terms of actual component temperature change.  If you see a good deal on QX fans, you get them and know you are not losing out.  

Edited November 28 by c-attack