corsair H100i pro high cpu temperatures

[stroeckx]

My cpu temperatures seem way too high, idling at 50-55 degrees.
As soon as there is even the slightest load, temperatures shoot up to 70-80 degrees.

Since that sounds like bad contact I took off the cooler, and the paste spread looked good as it covered the entire cpu.
I've reapplied it now but a lot of paste spread out, and it's still the same.

It's a 5900x on an aorus elite motherboard, with a corsair h100i pro, in an nzxt h510i case.

Water temperatures are 32-33 degrees at idle according to icue, so that seems fine.
Since I can pop off the radatior bracket in the case I tried tilting it and put my big room fan right on the rad, that didn't seem to make any difference either so airflow doesn't seem like a likely culprit here either.

Does anyone have a clue where to look for the problem? 

[c-attack]

Check your Vcore load at idle. Ryzen idles high to begin with, but a program may be keeping the core active. Have a look at the task manager and see if you can narrow it down. 
 

It does not appear to be AIO or flow rate related. If that were in play the coolant would continuously creep upwards at boot and not come back down until you power the machine off for a while. Specifically on the Pro model, you may need to be on balanced or higher for pump speed. The 1100 rpm Quiet preset is a bit slow for a large die, high core count cpu and the liquid will linger in the block too long for anything more than light desktop work. 
 

Any recent bios update or reset that might alter the voltage table?

[stroeckx]

well, there is some load on the cpu at all times, (nvidia broadcast, cam, icue, corsair services, etc), but they are all usually <1% so <5% overall.

The water temp of the aio seems fine inded, i had it on balaced at first but I put it on extreme now since discovering I have a temperature issue.
although I do notice that one of the two water tubes feels significantly warmer as the other.

I did just update my bios to install my new cpu, but after noticing my temps I compared my 3dmark result to my result before I changed anything, and my average temperatures are the same so I probably had this issue already.

[Corsair Notepad]

You have a mixture of things likely causing the higher temps. First the 5900X is known for being a warmer chip and the temps you detailed aren't outside the norm for it, and as c-attack pointed out depending on board you could be seeing higher VCORE voltages which assist with those higher temps. For example Asus is known for being more aggressive on the VCORE, also PBO will effect what you are seeing as well. You also have a very restrictive case when it comes to airflow which will lead to higher temperatures as well. The cooler is definitely doing its job and cooling the CPU though.

[stroeckx]

3 hours ago, Corsair Notepad said:

You have a mixture of things likely causing the higher temps. First the 5900X is known for being a warmer chip and the temps you detailed aren't outside the norm for it, and as c-attack pointed out depending on board you could be seeing higher VCORE voltages which assist with those higher temps. For example Asus is known for being more aggressive on the VCORE, also PBO will effect what you are seeing as well. You also have a very restrictive case when it comes to airflow which will lead to higher temperatures as well. The cooler is definitely doing its job and cooling the CPU though.

yeah, the 5900x is definitely a beast, but this isn't normal, it's definitely too hot.

As for the vcore, I've reset the bios (and re-enabled XMP), I don't think any cpu voltage settings were changed before.

I do get that the closed frontpanel of the nzxt 510 is a bit of a thing, I guess I should've done my research a bit better before buying it, but that's why I turned the rad and had a big room fan blow fresh air right at it, so airflow doesn't seem to be the issue either.

Any recommendations for what I could try?

[LeDoyen]

5 hours ago, stroeckx said:

well, there is some load on the cpu at all times, (nvidia broadcast, cam, icue, corsair services, etc), but they are all usually <1% so <5% overall.

That is enough to have the Vcore shoot up over 1.4V regularely, or permanently depending on how constant that load is. It's nothing you changed that's just how Ryzen works, and that's enough to get temperatures like the ones you see. That's why they are considered "normal".

If you have proper airflow, and the thermal paste spread is good (it should be from the factory, since it's pre-applied on the AIO), then there's just AMD's boost logic to blame.

They did quite a few updates late 2021 early this year to adress high idle voltages (and temperatures), so it could be worth it to check your motherboard's support page to see if you're on the latest bios version, and maybe update, to see if that makes a difference.

Past that, i would check tutorials for undervolting the CPU. It's a very common tweak for Ryzen users and you'll find tons of guides on youtube and other medias.

[c-attack]

As mentioned above, it doesn’t have to be a high cpu % to get the Vcore up. Specific instruction types or programs may keep the cpu from down clocking. That will be visible as max cpu frequency and high voltage. Try quitting CUE and the Corsair.Service and then something like HWinfo or HWMon to check out detailed Core frequency and voltage levels. 
 

8 hours ago, stroeckx said:

although I do notice that one of the two water tubes feels significantly warmer as the other.

However this I don’t like at all. In a functional cooler of any size, liquid temp drop through the radiator is going to be 1-2C. This should be imperceptible to touch. If you have one tube that is clearly warm and the other is not, that is a major red flag. This means coolant flow is not happening and the stagnant water is heating up the liquid from the block up. It would be very unusual for the coolant temp sensor in the block not to register the change, but we diagnose this for non-software coolers too. 
 

The next time you cold boot the machine after it has been off for several hours, take note of the cpu idle temp and coolant temp. It is normal for this to warm up 3-7C over the course of 10-15 min as the system components all warm up and so does the case. However, if your cpu temp starts at 35C and you can watch it creep up little by little to 55C, that is some type of flow problem.