Techpowerup: " Even when watercooled by our 360 mm AIO from Arctic, the temperature reached close to 100°C when fully loaded."
https://www.techpowerup.com/review/intel-core-i9-12900k-alder-lake-12th-gen/24.html
The problem is not the case it is the fact that a 240 AIO can't cool a 12900k under heavy load. What use case do you have? Handbreak, Keyshot or what other CPU intensive load? Another option could be undervolting or Power Limiting the 12900k.
We are aware. Hence just "thermal issues", NOT "thermal issues with the case". Thus also the though experiment (in reaction to other comments in this thread). As you may have or have not read, I already mentioned power limiting as an option, too.
Our particular use case / scenario is: Audio / Video editing, and streaming (ie. primarly DJing). Specifically, doing all that on CPU, because of all the funny driver issues with both AMD (OBS + AMD GPU encoding apparently is the worst choice, but Linux support is much much better) and NVidia (lets not open that can of worms).
A secondary use case is running multiple VMs and browsers during development. We've been doing a lot of really heavy-load backend development in the last few years, and the more CPU power, the merrier.
Third use case obviously is the reach for perfection
cu, w0lf.
ps: Originally I wanted to reply: lets maybe wait on the 12900 non-k, but the tests I could dig up so far look very.. naaaah. As in: Making the 12700k look much better.