Why can't I set the maximum RAM frequencies?

Question

Computers

All components (percentage, mother and RAM), according to the characteristics on the Internet, can operate at a frequency of 1333 mhz RAM, but in Bios I can only select Auto / 800/1066 MHz. Timings are set to Auto.
SDP tab in CPU-Z:
With two different dies the same situation, the RAM on the other PC runs at its own frequencies

Answer 1

This is already a limitation of the motherboard.
On laptops / corporate PCs / cheap MPs, BIOS is often very stripped down, with limited configuration features.