CPU runs very hot during Cinebench, can case be the problem?

[Haveri]

Hey everyone,

 

I’m dealing with an overheating issue on my desktop. During a Cinebench test, the CPU (i9-12900K) hits 100°C. I took it to a technician who reapplied thermal paste and cleaned the dust. Now, under the same load, it reaches around 92°C, still too high.

 

While I suspect the AIO (Cooler Master ML360 Illusion) might be faulty, the technician claims it’s working fine and suggests that the case might be too small and restricting airflow.

 

Here’s my question:
If I open the case and point a home fan directly inside, and the temperatures don’t drop significantly, can I safely rule out the case as the issue? I still have warranty on all parts and want to make sure nothing is underperforming or defective before accepting this explanation.

 

Any insight or advice would be appreciated!

 

My system (3 years old):

• Intel i9-12900K

• Cooler Master ML360 Illusion AIO

• ANTEC P82 Silent Mid-Tower ATX MM120X3

• Gigabyte Z690 UD AX

• Corsair Vengeance DDR5 64GB @ 5200MHz

Thanks in advance!

[leclod]

I couldn't find your case.

You using an AIO, I can't see how pointing a fan directly inside would change anything for the cpu.

Do you use a contact frame ? if not, do it now

Did you update your bios ?

Edited May 18 by leclod

[Haveri]

17 minutes ago, leclod said:

I couldn't find your case.

You using an AIO, I can't see how pointing a fan directly inside would change anything for the cpu.

Do you use a contact frame ? if not, do it now

Did you update your bios ?

Thanks, Sorry, I spelled it incorrectly, case is: ANTEC P82 Silent Mid-Tower ATX MM120X3

Because hot air from the radiator could theoretically build up inside the case? Otherwise the whole argument of a too small case is irrelevant right?

Yes I updated my BIOS. About contact frame, I'll look into it now

[jaslion]

20 minutes ago, Haveri said:

Thanks, Sorry, I spelled it incorrectly, case is: ANTEC P82 Silent Mid-Tower ATX MM120X3

Because hot air from the radiator could theoretically build up inside the case? Otherwise the whole argument of a too small case is irrelevant right?

Yes I updated my BIOS. About contact frame, I'll look into it now

Take off the front panel and see how much that does. This case has NO airflow because its "silent". Fyi noise padding doesnt sor when the pc gets louder because it cant cool itself. Defeats the entire purpose

[PDifolco]

It's a 12900k ... It uses like 250W+ at full load so reaches 90C+, seems pretty normal to me

[Haveri]

Thank you everyone!

[Ralfi]

On 5/18/2025 at 5:56 PM, Haveri said:

If I open the case in point a home fan directly inside, and the temperatures don’t drop significantly, can I safely rule out the case as the issue?

Which part of the case did you open, the front or the side?

 

That case is blocking the part where you want air to enter it - the front. It’s a poor design based on aesthetics over cooling.

Antec are trying to sell the idea that its vents allow enough air to enter the case…

 

I doubt their claims.

 

If you were to only open/remove the front of the case (leave the side closed) I think your temps would drop. But it’s still not ideal.
 

In an airflow-focussed case, 3 intake fans in the front & 2 exhaust fans (rear & top/rear) would let you keep both temps & noise down.