How to Calculate the FSB to RAM Ratio

Written by ruri ranbe
  • Share
  • Tweet
  • Share
  • Email

The front-side bus (FSB), also known as the system bus, facilitates communication between the random access memory (RAM), and the central processing unit (CPU). The CPU performs basic operations, like mathematical and logical calculations, and executes program instructions, while the RAM holds active data for the CPU to process. Achieving a 1:1 ratio between the FSB and the RAM is ideal for those intending to overclock their systems, as it's the most stable ratio. To calculate the FSB to RAM ratio, you must find the computer's FSB frequency, the RAM frequency and the rated FSB.

Skill level:

Other People Are Reading


  1. 1

    Restart or turn on your computer. Press the keyboard combination shown on the boot screen to go to BIOS set-up.

  2. 2

    Use the arrow keys to select "Advanced Chipset Features," "AI Tweaker," "Genie BIOS," or "Cell Menu," then press "Enter."

  3. 3

    Go to "FSB & Memory Config," "Frequency/Voltage Control," or "DRAM Configuration." Check the screen for the "Bus Speed," "FSB Frequency" and "DRAM Frequency" fields, and write down these numbers on a sheet of paper.

  4. 4

    Divide the FSB frequency by the RAM frequency, then divide the FSB frequency by the bus speed. Round both results to the nearest tenth.

  5. 5

    If either result has a number greater than zero in the tenths decimal place, then multiply each number by two. Round both numbers to a single digit to calculate the FSB to RAM ratio.

Tips and warnings

  • If you can't find the bus speed, RAM frequency or FSB frequency in the BIOS set-up, download and install CPU-Z. CPU-Z lists all the required information in the "CPU" and "Memory" tabs, and even shows the FSB:DRAM ratio on the "Memory" tab.
  • The BIOS set-up program varies from computer to computer. Check the documentation included with your PC or motherboard for further assistance, if necessary.

Don't Miss


  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.