Help me with major temp issues in a custom loop :(

[Sawtyss]

Hi,
this is my first post here, and the first time I'm actually asking for help w.r.t. liquid cooling... I thought I was handling it fine, but I guess not really, since my most current build is reaching temps in the 80s under load even before I start playing around with OC.

My current setup:
* [Case] BeQuiet Dark Base Pro 900
* [MB] MSI Z370 Gaming Carbon Pro AC (https://www.msi.com/Motherboard/Z370-GAMING-PRO-CARBON-AC.html)
* [GPU] EVGA GeForce 980ti Hybrid (https://www.evga.com/products/specs/gpu.aspx?pn=16add31d-8463-430a-a2a3-f9f1fd49e9a6) (original waterblocks removed, replaced with EKWB full cover block)
* [CPU] i7 8700k with EKWB Supremacy EVO waterblock
* [PSU] EVGA Supernova 1000 P2
* G.Skill Trident Z RGB 32G (2x16) 3200 (https://www.gskill.com/en/product/f4-3200c15d-32gtzr)
* Samsung 860 EVO M.2 (https://www.samsung.com/us/computin...rives/ssd-860-evo-m-2-sata-250gb-mz-n6e250bw/)
* Kingston SSD 500G

Loop is based around a 420mm radiator at the top of the case with intake fans, and a 280mm front facing radiator with intake fans as well.
Exhaust is handled by a single 140mm fan at the back of the case.

I've been previously using a 2600k cpu with a much older mobo, and my stress temps never hit over 50-55 degrees. Now I've cut down on the tubing significantly thinking that it would further reduce the temps cause the water spends more time in the rads compared to travelling, but after the change I am seeing alarming temps of up to 80-85 degrees under moderate load.

I did a 15 min torture test in Prime95 ending with an 83 degrees measurement on CPU sensor, and 94 on the MB sensor...

Below you can find the image of the assembled loop.


I'm not exactly sure what I did wrong to warrant such huge temps...
The only major difference I know I've made is that the front rad fans (2) are connected to the MB pins, while the top rad fans (3) are connected to the GPU PWM pins, and managed by the vanilla case fan pwm splitter.
Compared to my previous build, all the fans were managed by the GPU PWM via a non-vanilla splitted, but since the fans are spinning, and the stats claim they are doing their max RPMs, I don't think that that is the problem

Help?

PS:
Already done the regular checks.
I can't seem to find any indication of an air bubble somewhere (liquid level in reservoir is rock steady, no air bubbles anywhere).
I've temporarily disconnected the pump PWM cable so that it runs at its max setting, this did not help either.
I've set all the fans to 100% PWM - no help either.

 

[pastymuncher]

One thing I would try is to switch the roof fans to exhaust. At the moment you have 5x 140mm fans as intakes and only one as a exhaust so there is probably a lot of warm air sitting in your case that could be warming up your coolant. The 8700k is a hot running cpu and some people have had to delid theirs to get anything near decent temps. Have you tried remounting the block?

 

[Sawtyss]

Thanks for the reply!
Yes I've tried remounting the block with new paste applied (first time I tried a cross, second just a dot in the middle - after the first attempt and removal of the block the paste seemed to be spread quite thin and evenly).
I've also refilled the loop again just to make sure its not some air trapped somewhere - not much has changed.

I think you are right about the airflow though... I've temporarily removed the side panel of the case, and rerun the tests. Prime95 still gets the cpu very hot, but while gaming the temps were at a comfortable 60-65 degree range...
I'll try swapping the fans to exhaust - will let you know. I'm also planning on adding an intake fan on the side panel once I get a panel that actually has a fan slot...

 

[koooowweeee]

Could be that your CPU needs deliding. Have you tried remounting the CPU block? What temps are you getting on the GPU? If you get good temps on the GPU it's either of the first 2 that's the problem

 

[Sawtyss]

Temps on GPU never hit over 55 before the change, now with the new CPU they tend to be in the neighbourhood of 60. I'm guessing thats due to CPU heating up more. (thats all under load mind you).
I didn't think I'd need to actually delid it if I wasn't gonna OC it... This sounds really bad... Considering RMAing it now...

 

[Undesirable]

You don't need to delid it, you can run it at the temperature it reaches . Seriously though, Prime95 is going to cause a non-delidded Intel to reach those temps because AVX will definitely be on. You say you reached 80-85 degrees under moderate load... was it really a moderate load or Prime95, which is in no shape or form a moderate load?

 

[Sawtyss]

Sorry I think my post was a bit confusing...
I first noticed the high temps when gaming with the case closed up tight. The temp was in the mid 80s, which kinda got me alarmed.
Later on I removed the side panel to ease up the airflow in the case, and I was barely able to exceed 80s with Prime95, hence my conclusion that I need to improve the airflow quite a bit

 

[D1craig]

advice is all based on that top radiator having the fans orientation switched. as of now you are pushing all the air away from the exhuast fan and its probably struggling to be of any use.

top fans \/\/\/
front fans
<
<

so as you can see the air is being forced to the bottom of the case. with the top fans exhausting (you dont need to move them just turn them around ie. they dont need to be underneath the radiator).

/\/\/\
<<
<

EDIT - wow them around seem hard to understand lol. anyway its not hugely important but it might save you a few degrees of heat.

 

[Undesirable]

Isn't he taking in more cool air from the outside if all the rad fans are on intake? I'm not sure the air is being pushed quickly enough to force the air to the bottom of the case and keep it there. Surely the exhaust will still be able to do its job? But anyway, if it's an airflow problem then it's an airflow problem.

 

[Glanza]

Another thing to try with that case is remove the restrictive front off it, I can't remember who it was on here but they took the front off and temps dropped drastically, there isn't enough airflow getting in the front by design.

 

[Van_Dammesque]

Can you actually see a flow of water?
Tilt the case to get air locks out of the rads, as your pump may be stalling.

 

[Bugbait]

On a side note, there's still far more tubing than necessary. Decent pumps like a DDC or the D5 you seem to be using will have such a high flow that you can simply go for the shortest distance possible. Based on your picture I would recommend: Pump --> CPU --> GPU --> Front Radiator --> Top Radiator --> Reservoir.

EDIT: Or you could even swap the CPU and GPU so it's: Pump --> GPU --> CPU --> Front Radiator --> Top Radiator --> Reservoir

 

[vintage-x]

The drak base 900 isnt great for airflow. Its why I got rid of mine and swapped for a coolermaster 700p.

Even with 2 360 and 1 240 mm rads I was getting insanely high temps in the winter with the front and top on. With both off my temps went down about 15c on gpus and cpu

 

[Sawtyss]

Thank you very much for your tips guys.
I ended up installing two additional fans on the side panel, and now my temps are at 50-53 degrees while gaming
And thanks to pwm and the amount of mb pins I could set it up so that if the temps are below 45 all fans shut down, and pump slows down to 30%... Whisperquiet

 

[Disco_P]

Glad you sorted it but that tubing makes me want to cry.

 

[Sawtyss]

And what exactly is it that makes you want to cry?
Do you mean the way its laid out? The order of components?

 

[Lordgrayone]

It's just a looks thing it would be so much neater going res>gpu>cpu>top rad>front rad>res
But as long as you're happy it's fine

 

[Robzere31]

I have a similar layout as you can see.



Fan setup is as follows.

Rear, 140mm intake
Top 2x 140mm exhaust
Front 2x 120mm exhaust

Temps for GPX are usually 42-45c when gaming
CPU (7700K@5ghz delidded) 50-55c again whilst gaming.

Water usually around 32-35c

 

[ubersonic]

Your loop looks fine with the exception that the GPU block is flowing backwards but that's not going to cause a flow issue only raise GPU temps a bit. If your CPU is running too hot as it appears you say there's two quick tests you can do.

Firstly turn all your fans to 100% and try the torture test again, if that fixes it it's an airflow issue, if you still get the lava CPU temps that means the problem isn't cooling the loop so it must be flow rate or CPU block contact. Next test is to set the pump to 100% (if it's a Vario D5 turn the dial to 5, if it's PWM controlled set it in the motherboard BIOS/software) and try the torture test again, if you still get the lava CPU temps that means the problem is most likely the CPU block contact. Simply unscrew the thumbscrews holding the block to the board, slide it off, clean the TIM from the CPU/block, reapply and reinstall (you appear to have enough slack on your tubing to do this).

 

[D1craig]

i thought gpu blocks didnt have an orientation. atleast the ones i have had havent. an EKWB GTX 970 1 and an EKWB RX 480. neither had any instructions that even mentioned what direction if should flow.