Getting rid of the BIOS sounds awesome. I assume that means that it gets rid of code running the SMM, which can prevent invisible code from sapping performance from the machine for no apparent reason. For example, on recent AMD machines, such as my Zen 3 machine, memory bandwidth measured by ZFS' checksum algorithms will randomly drop by a significant percentage and there is no obvious reason why, although I suspect patrol scrubs are involved.
That begs the question. What does the patrol scrubs of ECC memory on your hardware?