Download CPUz here
On the mainboard tab it will tell you the BIOS version and the mobo brand/model. The mobo brand/model is also written on the mobo if you take the side panel off your case. It's generally located right above (or below) the x16 slot that the GPU sits in.
Once you know the mobo brand/model you can navigate to the manufacturers website to view available BIOS versions for your specific board.
I would agree that 100fps with no mods isn't on par for a 2080Ti, but those two mods better be pretty awesome to tank your FPS by 60%.
Are you running Minecraft with ray tracing on?