@redakula By looking at your xenpm start 1|grep "Avg freq"
output, this 5 GHz seems normal for your Ryzen 9 7900, because I can see at least 8 CPU threads already running on high frequency.
To get to 5.4 GHz you need less CPUs on high frequencies, you see the more CPUs are boosted at the same time, the lower the max frequency they can reach. For about 8-9 CPUs already boosted, 5 GHz seems reasonable.
So from your output I believe your CPUs are reaching the boosted/high frequencies without problem.
Thank you for your tests here on this.