9700k CPU running hot...

Camco

So, I recently bought a pre-built, as my options were limited to how I got my new PC. I've many in the past, but hard times makes decisions a little more complicated. Anyways...

So I got the PC delivered on Friday the 28th. Hated the layout of the case and the sketchy CPU, so I swapped them with parts I already had (Fractal Meshify C and a EVGA 750 G+ psu) Over the course of the weekend I was monitoring temps/speeds via CPUID and CPU-Z and noticed that my CPU is running almost constantly at 4.5ghz to 4.9ghz. This concerned me given the 9700k is supposed to be clocked at 3.6ghz and I have not done any overclock. For cooling, it is some cheap CoolerMaster 120mm AIO. I currently have 3 120mm intakes, and 3 120mm exhausts. 

Motherboard is an ASUS Prime Z390-P. I went to see if anything was set to OC, but I could not find anything, but maybe I am missing something. Any help would be appreciated as, I already ordered some better fans in hope to help combat this overheating issue, and not trying to spend even more on this system.

Additional info: CPU idles at 28-40c at 21.1C ambient. When gaming, my CPU was hitting 96C playing The Division 2 and Modern Warfare, before I shut it down.

Specs:
CPU: Intel Core i7-9700K
Mobo: ASUS Prime Z390-P
RAM: 32GB (8x4GB) Crucial Ballistix Sport @ 3000mhz
GPU: PNY nVidia GeForce RTX 2080 Super (blower style)
Cooling: Some cheap CoolerMaster 129mm aio
Fans: 2 Fractal 120mm, 4 Apevia fans

If any other information is needed, please let me know. 

TSTonyV

The clock speeds on your 9700k are very normal actually, the base frequency is 3.6GHz but the max turbo-boost for the 9700k is 4.9GHz which it will boost to automatically as temperatures allow. Your idle temperatures are fine, but hitting 90+ in gaming is pretty darn high. That's thermal-throttling territory which means reduced performance from your CPU.

First things first would be to replace the thermal paste and make sure the cooler is nice and snug on your CPU. You could also try setting a more aggressive curve for the CPU fan in your BIOS or via controlling software and see if that helps. 

Camco

Alright, I suppose that makes a bit of sense for the speeds.
I've replaced the thermal paste twice actually. The first time was because I wasn't sure of the factory application, and turns out it looked like someone used 3/4 of a tube of paste on it, and the second time, to ensure I had a snug fit. 
The Bios on this mobo has been a pain, but I did set more aggressive curves, and still getting up there in temps. About 20 minutes ago, from this comment, my AIO made a weird noise, and sounded like it came from the pump. Not sure what it was, but nothing I've heard before.

TSTonyV

Is the pump actually plugged into the CPU fan header or the AIO pump header on your board? If it's not, try moving it to that and setting the speed to be 100% and see if it makes a significant difference. The pump should be running at 100% all the time really. If that doesn't help, then I'm going to say it's likely the pump on your cooler is going out, especially if it's making strange noises. 

Camco

After talking to a buddy of mine, he told me to do exactly what you stated. It was plugged into the pump header, so we changed it out. Was still getting terrible temps. Ordered a Noctua NH-U12 Chromax, which came in the mail today (technically yesterday now), and I dropped from mid 90s to barely over 70C in most cases, with a fairly aggressiveness curve. I am going to assume the AIO in my prebuilt was just bad as they apparently do NOT test their full systems before selling. Either way, problem solved. Thanks for the insight, got me learning a few things these past two days. 

TSTonyV

Yep, that sounds about right. Probably a bad pump leading to bad circulation. Happens once in a while unfortunately.