I have a 7950x with 5 radiators, 280mm 45mm thick, 2 x 280mm 30mm thick, 360mm 30mm thick and external 560 45mm thick and still sits at 40 degrees doing nothing, at PBO I get max 5.6ghz with 60 to 70 degrees, all core 5.1ghz at 85 degrees, I can overclock to 5.4 and 5.3 ghz and hit 95 degrees and topped cinebench water cooling with 39516, I will never be able to get 5.7ghz and above
Forget about overclocking such a modern CPU.
You have the best cooling that you possibly can (unless it has some contact issues), so just set PBO to auto, and enjoy.
Don't worry about idle temps, either. These CPU cores have an incredibly small surface area, which means they cannot transfer the minimal heat that they make at idle to the IHS and your cooler effectively. 40 °C idle
with any kind of cooling is normal.
Oh, and welcome to TPU!
I am sure there can be things tweaked in the proces, as i challenged myself to keep my 2700x at all times below 60 degree mark to hit the constant 4.25Ghz all core or 4.4 single thread.
1: good mounting pressure. A washer really helps. But i'm not sure about long term effects for motherboard or socket.
2: good thermal paste. There's really good ones out there, my choice was MX-5
3: push pull fan configuration on a 360mm rad with fairly aggressive fan-speed
4: negative voltage offset; basicly voltage tuning. The less you need the less heat.
I'm sure you can do even more, such as lapping or even IHS removal but those obviously jack your warranty.
1: Unnecessary. Coolers and coldplates are designed with the optimal mounting pressure in mind.
2: MX-5 is a hit-and-miss. Some batches have terrible separation issues. Not recommended. MX-4 is much better and more reliable. If you have money to spend, TG Kryonaut is even better.
3: Push-pull isn't necessary. A good fan curve does the job, although even that only saves you a couple of degrees max.
4: Agreed, though one really needs to know what they're doing. I think, cooling your CPU with 5 radiators is overkill enough not to warrant any need for voltage tuning.