GameBoost is one of the
worst functions in the entire BIOS. That's because it is a completely generalized, cookie-cutter auto-OC mechanism that tries to overclock any CPU using brute force, no matter how well-suited it is for it in terms of added voltage etc., or how it behaves individually (each CPU is different). This function always does more harm than good to the way the CPU is running.
Do not worry about the speed shown in the BIOS, the 3.2 GHz shown in the BIOS are only the CPU's base frequency, so for a 14900K, that is 3.2 GHz. However, this base frequency is irrelevant, as it will clock much higher under load in Windows (up to a crazy 6 GHz according to the load), and much lower when there is no load (like 0.8 GHz, for power saving). So pay no mind to the CPU speed shown in the BIOS on the top left, you will hardly ever see that speed in Windows.
To properly optimize the way the CPU is running, especially nowadays with a high-end 14th gen CPU, you should go completely in the other direction. Because if you undervolt a little, not only do you make things much more manageable and less dangerous regarding the voltage, you can also gain some performance, completely without overclocking. That's because the high-end CPU (and GPU) models are all pushed too far from factory. Intel, AMD, NVIDIA, with their high models, they only want to win benchmarks in the launch reviews, they don't care about power draw or efficiency. But if you reduce the voltage a bit to what your specific CPU actually needs, then it has a lower power draw, and all of a sudden, it can use that to boost higher and increase their perforance within the available power budget (or temperature budget). Not to mention it will basically run better than ever before.
I explain how that works in my
Guide: How to set good power limits in the BIOS and reduce the CPU power draw.
It is of great importance that your BIOS is updated to 7E06vH7 first, from
https://www.msi.com/Motherboard/Z790-GAMING-PLUS-WIFI/support
This is to avoid the severe
stability/deterioration issues with 13th/14th gen. Read more
here.