Well, to start with, you have a cooler that lacks having good performance.
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Adding to that is the fact that you have an ambient temp that is very high at 30-40°C.
This is compounded by having an MSI motherboard that does NOT have the sort of outstanding VRM configuration they put on their Previous Gen B450 and X470 boards, but charged more for, and are very disappointing.
Altogether, I'd say you are experiencing some form of thermal throttling, probably due to VRM or chipset temperatures, but there ARE a few things you could do about it to try and help alleviate some of it.
First, go to the AMD website, download and install the latest AMD X570 chipset driver package. Don't use the one from the MSI website, use the one from AMD.
Next, restart the system, then go into the Windows power plan and make sure that the Ryzen balanced plan is selected. Then click on "Change plan settings", then Change advanced power settings, then expand "Processor power management" setting and set the minimum to 5-8% if it is not already set to that. Save settings and exit the power applet.
Go into the BIOS and make sure all of the following are set as recommended.
Enable Cool N Quiet
CPPC preferred cores - Enabled
Advanced or Global C-states - Enabled
Make sure you have your memory installed in the 2nd DIMM slot over from the CPU and the 4th DIMM slot over from the CPU. This is important. Also, make sure that A-XMP or XMP is enabled in the memory section of the BIOS.
Beyond that, we need to know what case you have, how many case fans you have and how you have ALL of them arranged including location and direction/orientation?