Unlocking Performance: What is FCLK Frequency and Its Impact on Your System

June 11, 2023 0 By tech

FCLK, or Fabric Clock, is a fundamental term when it comes to understanding the architecture of modern processors, especially those designed by AMD. Its implications for system performance, overclocking potential, and overall PC functionality make it a critical concept for enthusiasts and experts.

Defining FCLK

FCLK stands for “Fabric Clock.” It’s the frequency at which the Infinity Fabric – AMD’s proprietary interconnect technology – operates. This frequency is responsible for communication between the processor’s different cores and with other elements such as memory (RAM).

The Infinity Fabric clock speed has a significant impact on the system’s performance. It can influence the speed of data transfer between cores and to the memory. So, a faster FCLK can lead to improved performance, particularly in applications that require high data transfer rates.

How to Check Your FCLK Speed

There are several software utilities available that allow you to check your FCLK speed from within your operating system. Here are a few recommended ones:

  • CPU-Z: This is a free utility that provides a wealth of information about your system’s hardware. The ‘Memory’ tab in CPU-Z displays the DRAM frequency, which should be half of your FCLK speed if they are synchronized.
  • Ryzen Master: If you’re using an AMD Ryzen CPU, the Ryzen Master utility is a great tool. It provides detailed information about your CPU, including the FCLK speed.
  • HWiNFO64: This is another comprehensive system information tool. The FCLK speed can be found under the ‘CPU’ section.

Note: Always download software utilities from trusted sources to avoid malware or unwanted software.

Understanding the Relationship Between FCLK and Memory Clock (MCLK)

The performance of a system, particularly one using AMD Ryzen processors, can be significantly influenced by the relationship between the FCLK and the Memory Clock (MCLK). Ideally, these two should be operating at a 1:1 ratio to optimize system performance.

For instance, if your memory is running at 3200MHz, then the ideal FCLK frequency would be 1600MHz (since DDR memory is “double data rate,” its effective speed is half the stated rate). Running these two out of sync can potentially lead to a decrease in system performance, and might cause stability issues.

FCLK Frequency for Various Ryzen Processor

  • The Ryzen 3600 can reach an FCLK frequency of up to 1800 MHz.
  • The Ryzen 3900X has a maximum FCLK frequency of 1800 MHz.
  • The Ryzen 5000 series can achieve an FCLK frequency of up to 2000 MHz.
  • The Ryzen 5600X has an FCLK frequency range of 1800-1900 MHz.
  • The Ryzen 5800X can reach an FCLK frequency of up to 2000 MHz.
  • The Ryzen 5900X also has a maximum FCLK frequency of 2000 MHz.
  • While the Ryzen 3700X typically reaches up to 1800 MHz, it can be overclocked to around 1900 MHz for its maximum FCLK frequency.

Table that shows the FCLK frequencies for the Ryzen processors you asked about:

ProcessorFCLK Frequency
Ryzen 3600Max around 1900 MHz​
Ryzen 3900xMax around 1600 MHz​
Ryzen 5000Can be overclocked to 2000 MHz​
Ryzen 5600xCan hit only 1800-1900 MHz​
Ryzen 5800xCeiling of 2000 MHz​
Ryzen 5900xCeiling of 2000 MHz​
Ryzen 3700xMax around 1900 MHz​

Please note that these values may vary depending on the specifics of the individual processor and system. This is especially true for values that depend on overclocking, which can vary widely depending on many factors, including the specific piece of hardware, the cooling system used, and the skill of the person doing the overclocking.

FCLK Frequency for 3000mhz, 3200mhz, 3600mhz, 4000mhz, 6000mhz RAM

FCLK, or Infinity Fabric Clock speed, in AMD’s Ryzen processors generally needs to run at a 1:1 ratio with the memory clock (MCLK) for the best performance. The memory clock is typically half of the rated speed of DDR (Double Data Rate) RAM. So for example, if your RAM is rated at 3200MHz, the actual memory clock is 1600MHz, and thus the optimal FCLK would also be 1600MHz. This 1:1 ratio is generally recommended up to 3600MHz RAM. Beyond that, the ability to maintain a 1:1 ratio can depend on the specific processor and motherboard.

  • For 3000 MHz RAM, the FCLK frequency would be around 1500 MHz.
  • For 3200 MHz RAM, the FCLK frequency would be around 1600 MHz.
  • For 3600 MHz RAM, the FCLK frequency would be around 1800 MHz.
  • For 4000 MHz RAM, the FCLK frequency would be around 2000 MHz. Note that this is typically the upper limit for FCLK frequencies, and achieving this may depend on the specific capabilities of the CPU and RAM.
  • For 6000 MHz RAM, the FCLK frequency would be around 3000 MHz. However, achieving this would likely require significant overclocking and may not be possible with all hardware.

Let’s put these details in a table:

RAM Speed (MHz)MCLK (MHz)Recommended FCLK (MHz)

*Note: For RAM speeds above 3600MHz, it’s possible that some processors may not be able to maintain a 1:1 FCLK:MCLK ratio. This can depend on the specific processor, motherboard, and even the quality of the individual chip. Running FCLK at a 1

Note: The above table is a simplification and actual ideal frequencies may depend on specific CPU models and other factors like BIOS settings and quality of the memory modules.

Factors Influencing FCLK Speed

Here are some of the key factors:

  1. CPU Model: Different CPUs have different bases and maximum FCLK speeds. The specific model of your CPU will determine the range of FCLK speeds that you can achieve.
  2. Motherboard Quality: The quality of your motherboard can also impact the FCLK speed. Higher-quality motherboards often have better power delivery systems and are better equipped to handle higher clock speeds.
  3. RAM Speed: The speed of your RAM can also influence the FCLK speed. Generally, faster RAM allows for a higher FCLK speed.

How Does FCLK Affect Gaming?

When it comes to gaming, every millisecond counts. A slight delay in frame rates, a second longer in load times, or just the smallest hitch in the graphics, can make all the difference in your gaming experience.

The Relationship between FCLK and Gaming

Now that we understand what FCLK is, let’s delve into its impact on gaming. Games are complex pieces of software that require constant communication between the CPU, memory, and GPU (Graphics Processing Unit). This communication is crucial for rendering graphics, loading new areas of the game, and processing game physics.

A faster FCLK means faster communication between the CPU and memory, which can lead to:

  1. Reduced latency: Faster communication can reduce the time it takes for data to travel from the CPU to the memory and vice versa. This reduced latency can improve game responsiveness and reduce input lag, which is crucial in fast-paced games.
  2. Improved frame rates: A faster FCLK can also potentially lead to higher frame rates in some games. This is particularly true for games that are CPU-bound, where the CPU’s performance is the limiting factor in the game’s frame rate.
  3. Faster load times: Faster communication between the CPU and memory can also lead to quicker game load times. This is especially beneficial for games with large open-world environments that constantly load new data into memory.

Important Note: While a higher FCLK can improve gaming performance, it’s not the only factor at play. Other components, such as the GPU and the speed of your memory (RAM), also play a significant role.

How to Optimize FCLK for Gaming

Optimizing FCLK for gaming involves adjusting the FCLK speed in your system’s BIOS (Basic Input/Output System). Here’s a general step-by-step guide on how to do it:

  1. Restart your computer and enter the BIOS. This usually involves pressing a specific key (like F2, F10, or Del) during the boot process.
  2. Once in the BIOS, navigate to the settings for your CPU or Infinity Fabric.
  3. Find the setting for FCLK or Infinity Fabric speed.
  4. Increase the speed in small increments, saving and testing stability at each step.

For a more comprehensive guide on how to overclock FCLK, you can read this How to Overclock FCLK article.

Tips and Tricks for FCLK Optimization for Gaming

Here are some tips and tricks for optimizing FCLK for gaming:

  1. Match Your FCLK and Memory Speeds: If possible, aim for a 1:1 ratio between your FCLK and your memory speed. This can help to reduce latency and improve gaming performance​.
  2. Check Your Motherboard’s QVL: Your motherboard’s QVL (Qualified Vendor List) can provide a list of memory kits that have been tested and approved for use with your specific motherboard. Using a memory kit from this list can help to ensure compatibility and optimal performance​.
  3. Consider the Impact of Heat: Pushing memory timings too far can lead to increased heat, which in turn can cause the CPU to throttle back its clock speed. Always monitor your system’s temperatures when overclocking, and consider the potential trade-off between memory performance and overall system performance​.

In conclusion, FCLK can have a significant impact on gaming performance, particularly in games that are CPU-bound or that require frequent communication between the CPU and memory. However, optimizing FCLK for gaming is not a straightforward process and involves careful consideration of various factors, including memory speed, CPU temperatures, and motherboard compatibility. As always, proceed with caution when overclocking, and happy gaming!

Understanding FCLK Frequency for Early Power On

The FCLK or Fabric Clock frequency is a critical parameter in the power-up sequence of a computer’s central processing unit (CPU). This frequency controls the speed at which data can be transferred between different components within the CPU. In this blog post, we’ll explore the importance of the FCLK frequency, its role in early power on, and how to optimize it for better system performance.


Understanding FCLK frequency and its impact on system performance is critical for anyone looking to get the most out of their AMD-powered PC. Remember, the key to optimizing FCLK lies in maintaining a 1:1 ratio with your memory clock, and as with all overclocking endeavors, caution and careful monitoring are your best friends.