high CPU and water temp

[Schlass]

Hi, 

I recently build a new loop and ran into a problem with my temperatures. 

I have a 3900x with a 2080 ti cooled by 1x 360/30mm rad in the front and a 120/30mm rad in the back. But for some reason my CPU 

temps are in the 80s under load (only CPU) and the tubes get quite hot to the touch. I adjusted the CPU voltage to 1.21 volts because the default seemed to be 1.49ish.

I really don't get why the temps are so bad... The pump seems to be running because I can see the waterflow in my Res. 

[GER_T4IGA]

Have you tried increasing pump speed?

You might have to remount the block. I just recently had to do that. Temps dropped by 10C across the board and the same might happen here.

 

Also what lead are you using. In normal operation I barely see 70C sometimes but under prime I hit 89C. 3900X, custom loop 1.28V 4.225GHz

I know, settings are not that easy to compare, just some pointers.

 

Also: you should definitely get a temperature probe for your water. They come in rigid fittings you can use like 'extenders'.

[Deli]

19 minutes ago, Schlass said:

Hi, 

I recently build a new loop and ran into a problem with my temperatures. 

I have a 3900x with a 2080 ti cooled by 1x 360/30mm rad in the front and a 120/30mm rad in the back. But for some reason my CPU 

temps are in the 80s under load (only CPU) and the tubes get quite hot to the touch. I adjusted the CPU voltage to 1.21 volts because the default seemed to be 1.49ish.

I really don't get why the temps are so bad... The pump seems to be running because I can see the waterflow in my Res. 

1.49v for all core load? Seems unlikely, because your CPU will catch fire with such high voltage. More likely it's on one or two cores load. And the voltage only apply to that one or two cores. All core load the mobo will adjust the voltage to 1.2 something volt.

 

What is the ambient room temp? I ask because it's summer now. Adding radiator space will reach a point of diminishing return. I started with a single 280mm rad, then added an extra 240mm. The temp only drops a further 2-3C. My CPU also hits 80C in the recent heat wave(my room has no AC). Normally it runs at 70C in Blender render.

[Deli]

Worth to mention. Is your loop running in the correct direction? I mean the CPU block has intake and outlet. I once connected it incorrectly. And the CPU ran ~4C hotter.

Second, if the outlet tube gets quiet hot to touch. It's an indication the flow rate is too low. Something is restricting the flow in your loop.

[Schlass]

Thank you for your quick replies

My Room temperature is about 21 degrees C. I have the pump running at 1600rpm and all 4 fans at around 1000-1100 rpm. from the looks of it the flow seems fine from what I can see in my res... And yes it seems that I got the inlet and outlet of the cpu block mixed... But can that really be the reason that my CPU is hitting 80C in Aida64 (only stressing CPU,FPU  and cache)? When the GPU only is at 100% load (also with Aida) it settles in around 50 to 55 Degrees and when I stress both cpu and gpu the cpu even goes into the 90s... which is of course expected with the added heat of the gpu. But how can the GPU be cooled just fine and the CPU is almost burning when I stress them seperately.. I mean a 2080 ti isn't the coolest GPU out there...

 

Edit: Added picture of my loop and video of res. Flow is: Res->Pump->GPU->CPU(I know not optimal but that bad?)->120Rad->360Rad->Res

Edit 2: Also I checked the CPU Block seating and it seems to be mountet correctly. The thermal paste spread very evenly.

Edit 3: Another thing that confuses me is that the CPU runs at 35C idle and when I start the stress test in Aida it instantly jumps to 70C. I built a few loops now and never had anywhere near those thermals..

 

 

IMG_0671.MOV

[Lipe123]

Zen 2 chips run hot, idk why no one mentions this.

 

My R5 3600 jumps immediately to 70-80 degrees under load with a custom loop. Because of the dense 7nm architecture the heat cant be moved to the block fast enough.

[Deli]

11 minutes ago, Lipe123 said:

Zen 2 chips run hot, idk why no one mentions this.

 

My R5 3600 jumps immediately to 70-80 degrees under load with a custom loop. Because of the dense 7nm architecture the heat cant be moved to the block fast enough.

It seems there is some variation among chips. Look at reviews usually they don't run too hot. However quite a few people find their chips run pretty toasty.

 

I built a second rig recently to aid my work flow. Which has a 3600 in a Cooler Master NR200. I tried out three coolers. The first one is Noctua U9S. Which is fine for stock or OC to 4.2GHz with a targeted load temp of 75C. If I want to OC to 4.3GHz, I need a bigger Scythe Mugen 5. I have a spare 240mm radiator, fittings and CPU block laying around from an old build. So I also put together a 240mm loop. Which allows the CPU to run below 75C at 4.4GHz.

[Deli]

11 hours ago, Schlass said:

Edit 3: Another thing that confuses me is that the CPU runs at 35C idle and when I start the stress test in Aida it instantly jumps to 70C. I built a few loops now and never had anywhere near those thermals.

My rig behaves more or less the same. It idles at 35C, and jumps straight to 65C when starts a stress test. After 10 min, it'll stabilised at -70C.

 

GPU always run a lot cooler if water cooled. You may think the 2080Ti pumps out 260w. It will be harder to cool than the CPU. The fact the GPU block has direct contact with the die. And the GPU die is huge, that means the heat density is lower. It's common the GPU runs 50C or lower when water cooled.

 

I have a suspicion that something isn't quite right with your CPU block. In the last resort, may be you can take it apart and have a look if there is any debris or defect inside the CPU block.

 

The sequence of the loop doesn't matter at all. Putting radiator in front or after CPU/GPU block doesn't make any difference to the cooling.

 

Last question. What case do you have? Is it with solid front panel or tempered glass? For e.g. Phanteks Evolv X is notoriously bad for cooling, because it's so restrictive for air flow.

[Schlass]

14 hours ago, Deli said:

GPU always run a lot cooler if water cooled. You may think the 2080Ti pumps out 260w. It will be harder to cool than the CPU. The fact the GPU block has direct contact with the die. And the GPU die is huge, that means the heat density is lower. It's common the GPU runs 50C or lower when water cooled.

Yeah that makes sense. I didnt think about that

 

I swapped the order and that actually made a 10 degree C difference. Now the order is:

res->pump->GPU->360 Rad-> CPU -> 120 Rad -> Res

 

I have my CPU running at 4.2Ghz @ 1.2125 Volts and it settles around 77C in Aida after testing for 3 hours (CPU only) but then the fans are pretty audible...

 

14 hours ago, Deli said:

I have a suspicion that something isn't quite right with your CPU block. In the last resort, may be you can take it apart and have a look if there is any debris or defect inside the CPU block.

 

Last question. What case do you have? Is it with solid front panel or tempered glass? For e.g. Phanteks Evolv X is notoriously bad for cooling, because it's so restrictive for air flow.

I have a very cheap block from alphacool lying around. I could test it with that one...

And for the case I'm using the fractal meshify C, but even with sidepanels off CPU temps aren't really affected (2 degrees max). I have the front fans configured as intakes and the rear 120mm as exhaust and another 140mm at the top, also as exhaust.

 

Thank you all again for your input  

[Deli]

You have the 3900X at 4.2GHz. 77C is very reasonable. I run mine at default with -0.05v undervolt. It usually stays at 4.025GHz when stress test. That's enough to explain the difference in temperature. 77C vs 70C. Mine is running lower clock speed.

[narrdarr]

On 8/30/2020 at 1:03 AM, Schlass said:

And yes it seems that I got the inlet and outlet of the cpu block mixed.

GpU block also technical doesn't have specific way to flow through the block, but it is advisable for the water to flow through the plate then the final. It might help a little and if you are going to fix the CPU flow direction might as well do this too.

 

Some extra info on TR CPU blocks. Might be useful at or just a good read.

https://www.xtremerigs.net/2018/08/29/amd-threadripper-cpu-block-review-round-up/