my Ryzen 5 3600 with stock cooler and settings is significantly underperforming its boost clock in Cinebench R23, and also underperforming its average Cinebench score by a lot. I believe this to be due to thermal throttling when the CPU hits 80-95 degrees it tends to drop the clock speed down to around 3950MHz. I have no idea why my CPU is doing this, my GPU(5700xt) has very solid thermals in the 60s, so I don't believe it's my case(NZXT h510i). my motherboard(Asus b550m-A wifi) also posts solid thermals and so does my ram(32GB 3600mhz). All of my drivers and bios are up to date and fresh. Please if you know anything about a problem like this help.
The AMD stock coolers are best described as 'adequate.' I was running a 3600X with a wraith prism and was getting higher than I liked temps so I swapped the cooler for a be quiet dark rock slim and noticed an immediate difference. Any decent air cooler will help with your thermal throttling.