One possible explanation about why a CPU better than another one performs worse is related to thermal paste (or pads). If it is an option, try to replace the paste or pads. Notice the fact that I shoot in the dark here. It might be something else (even the power supply or MB problem) but replacing the thermal paste can't hurt and offers 50% chances to fix the issue. The thermal paste (pads) have the capacity to transfer the temperature to heat sink as fast as possible before the thermal throttling kick in. When thermal throttling happens the CPU reduce the power in order to prevent physical damage and even the sensor fails to report the sudden temperature spike. Temperature sensors and monitoring (similar to "The average CPU temperature is 70°C") will only mislead, as it is unable to report the temperature spikes.
Appreciate the idea, but the PC does not have issues with overheating or performance in any other title, even ones with worse optimization than Veilguard. I also tried limiting CPU max usage to avoid throttling, in case that was the problem, since before the last patch CPU was at max temperature for many users, and it made no difference.
It's an incompatibility with the game. Spiderman used to run at 10 fps at min settings before it was patched more than a year later, after which it ran perfectly at 60 fps on high.
I did said "shooting in the dark". Try using HWinfo64 and activate different sensors. It might provide new information with a 5 min graphic log.
Edit
Tried deleting shader cache
Which cache you delete? Nvidia, system or game caches?
Deleted all of them.
