The chassis' design is hindering airflow to the cpu. The gpu appears to be holding up well though.
A top-down air cooler isn't what I'd call adequate for a cpu of that caliber. [I'm assuming it's a top-down model from the images I looked up.]
Probably the best thing you can do here - period - without having to spend any money:
Windows Search > Edit power plan > Change advanced power settings > Processor power management > Maximum processor state. Set it to like 98-95%, click Apply and exit.
As for spending money, I have 3 ideas, but it's highly likely that the proprietary motherboard smacks at least 2 out of the 3 ideas to the ground for one reason or another.
It's anti consumer by trapping you into only making changes/upgrades to the PC through the company.
1)Corsair H80 or Arctic Liquid Freezer II 120. These need a couple extra headers that probably aren't present on a motherboard like that.
2)A larger air cooler should fit, but... HP doesn't disclose the available clearance for that... because they don't want you changing it - at least, not on your own, and you probably can't take out the mobo without ripping out some other cable.
3)A new, more airflow friendly chassis. That board likely has front panel connections that will not work in other chassis, making a new chassis useless.
I'm just going to strike them all out. There's just no way around what HP did.
If nothing else, the thermals you see are 'acceptable'. The edit power plan suggestion is probably the best thing you can do to get them within your comfort zone.