How to Change the MHz for Your RAM on BIOSby Theon Weber ; Updated February 10, 2017
The frequency of a stick of RAM, measured in megahertz (MHz), represents the speed with which information moves between it and other parts of the system. This frequency relates to the maximum frequency supported by a computer's motherboard, but can sometimes be changed using the BIOS firmware.
Restart your computer.
Watch for a message along the lines of "Entering Setup." This message will appear shortly after your computer turns on and varies in its particulars from system to system. It will mention a keystroke or series of keystrokes that will access the BIOS.
If an image—a company logo, for example—appears instead of useful text, press the ESC key to remove it.
Press the BIOS access keys.
Change RAM Frequency
Search your BIOS for a RAM frequency setting. Again, the precise location varies depending on your system, but it's often in an "Advanced Chipset" section, on a page that mentions RAM or DRAM configuration.
Modify the RAM frequency, which is the value expressed in MHz.
Exit the BIOS with the "Save Settings and Exit" option and let your computer restart.
As mentioned above, many prefabricated computers, such as those sold by Dell or HP, have locked the RAM frequency at the factory and removed the setting from BIOS. Motherboards with cleared BIOS or those sold separately for use in building your own computer will have this setting available.