Ryzen 9 3900 @ 3.10 Ghz

The Ryzen 9 3900 (non-X) is currently operating at its base clock speed of 3.10 GHz, failing to reach its advertised maximum boost clock of 4.3 GHz. Despite attempts to manually overclock the CPU using Ryzen Master, where it successfully ran at 4.3 GHz with 1.45V, I encountered issues after about 30 minutes—where the clock speed dropped drastically to 0.55 GHz and remained stuck there. A hard reset by unplugging the PC temporarily restored the clock speed back to 3.10 GHz. It's unclear whether this problem is due to the CPU itself or the Biostar B450MHP motherboard, which is running the latest BIOS. Additionally, I enabled Precision Boost Overdrive in the BIOS for automatic clock boosting, but it didn't seem to yield any improvement in performance. This situation leaves me perplexed about the root cause and potential solutions.