In that thread, you get to learn how you can run latest chromium on Maverics. Firefox is a toast now. General rule of thumb being don't run old OS and old browser on internet-facing machine.
you could still get mac minis that would run 10.9 officially without the headaches. (2012 vintage ...)
EDIT: There are drivers missing for newer hardware in 10.6-10.9. Haven't tried if OCLP could help with this.
Why would it be? AFAIK the latest x86 CPUs, despite using EFI BIOS, still start off in 16-bit realmode at the reset vector, and most if not all of the BIOS code is going to be 32-bit protected mode code.
