High BIOS idle temperature at cold - normal or not?

[HighNiner]

Brand new setup:

ASUS ROG Strix Z790-E Gaming WiFi II

Intel i9 14900KF

NZXT Kraken 360 AIO water cooler.

NVidia GeForce 4070 Ti VENTUS 2X OC 12GB

Latest BIOS installed

No Operating System installed yet

My idle CPU temp from cold start/boot is 49°C.  There are a few things I have changed in the BIOS as recommended by a few videos I've watched on YouTube (https://www.youtube.com/watch?v=s43Auv8ub7w) - but nothing changes the idle CPU temperature.  Is idle at 49°C normal?

Could the problem be too little or too much thermal paste?  Maybe there's an issue with the AIO water cooler? 

[KrissyG]

with water cooling you should be getting 8~10°C over the room temperatue if CPU is idling.
So at 20°C room temperature, fans on the AIO at lowest speed, then the CPU package should be at 28~30°C.

Check the following:
- thermal paste on the CPU and if you tightened the water block good enough
- apparently some CPUs don't have a flat surface, so a contact frame would not hurt
- no air trapped in your AIO, is pump working as it supposed to'? is the water block clean and nothing blocking the water flow?
- are the AIO fans blowing the air out of the PC case?
- idle power consumption, CPU TDP at idle should not exceed 5~10W 
- is teh CPU frequency constantly locked at over 5GHz when the PC is idling?

49°C at idle is definitely not normal.

This is what you want to see:

[HighNiner]

Thanks for your reply @KrissyG 

I have now installed Windows 11 Pro and installed the software for my NZXT Kraken 360 AIO water cooler.

The CPU temperature now idles around 28°C and the water cooler temperature idles around 22°C.  All the fans are quiet and only speed up when the PC/CPU is working hard.

I think this is now ok.

Thanks again.

[KrissyG]

i keep on forgetting that AIO's have a dedicated software, i never used the motherboard to control the water cooling.
I use standalone fan controllers for teh water cooling, so software crashing or updates have no impact on the cooling at all.

Yes, 28°C idle is exactly spot on with room temps close to 20°C, i also get 22~23°C water temperature.
So it was either the OS or the software provided by the NZXT, interesting. 

[HighNiner]

As a way of an update, when rebooting Windows to enter the BIOS, the CPUT temp goes to about 48/49°C.

I'm guessing the Motherboard/BIOS isn't in control of the fans OR the BIOS automatically puts the fans at full speed.  There's 3 140mm fans on the AIO radiator, a 140mm fan blowing into the case located at the top of the case and a fan at the rear of the case used an an exhaust.

I have done a complete new Windows installation - this time I haven't installed any software from NZXT to monitor the fans.

However, the fans are quite until the PC starts doing some work so I'm happy now there isn't any issue with an incorrectly installed AIO water cooler.

Thanks again for your help.

[KrissyG]

well i didn't do anything. Btw, if you have 4 fans pulling air out of the PC case, and only one blowing air in it, then that will not work as well as it could.
If that 'exhaust fan' is also blowing air out.....then i wouldflip it and let it blow air inside, AIO will have more air to grab with less strain.

[HighNiner]

The radiator is vertically mounted at the font of the case with the flow/return hoses located at the top -- the pump head on the Intel chip is lower than the top of the top of the radiator.

I watched many videos on YouTube about which are the best positions for fixing the radiator.  At the top of the case was preferred position but there's a metal heatsink/shield that prevents me from mounting the radiator on the top of the case.  Fixing the radiator to the front of the case and vertically mounted is 'ok' according to many videos.

The only location which is a total No No is fixing the radiator at the bottom of the case as this causes air bubbles to form and get stuck in the pump head - massively reducing its cooling ability.

So, the radiator has 3 140mm fans sucking air 'IN' (blowing onto the radiator), one fan on top of the case blowing cold/room temperature air into the case and one fan, another 140mm fan is an exhaust (sucking any air out of the case).

[KrissyG]

I see, if i were you i would fix it at the top of the case regardless, even if i had to use zip ties. Theoretically, when it's at the top, the radiator could run in passive mode without the fans being on, as the warm air rises it would create an air movement cooling the radiator slightly.