Testing Philosophy

Objective review goals are to test system memory using a real world configuration and use-case for all types of consumers. These reviews focus on providing an accurate representation, setting realistic expectations using a wide range of benchmarks to showcase the best and worse of the product in question. To accomplish this, some accommodations had to be made. To produce repeatable results variables must be accounted for and taken into consideration during testing. For example, the processor is locked to a set frequency to rule out CPU Turbo as a factor. System memory's Primary and Secondary timings are also observed to make sure that it is accurately applied when XMP/EXPO Profile is enabled. If the motherboard in question does not apply these timings correctly, they are manually entered. Random spot check validations are performed comparing previous results to make sure they are still the same as before, which lowers the probability of bad data entries throughout large data sets.

One variable that cannot always be fully controlled is the graphics card. This is because it uses a clock frequency curve based on temperature, voltage and power draw. However, benchmarks are run in a specific order to ensure every memory kit has the same starting point. Room temperature is also monitored to ensure a minimal impact on performance. Once again, the overall goal is to have the least amount of variables while testing, since they can skew the results.

What does it mean to be GPU Bound?

The most common misconceptions and inaccurate information on how memory impacts gaming performance is the lack of technical understanding what it means to be GPU bound. It has a very simple core concept, but with many variables that need to be factored in for an accurate assessment. First, let's start with a generalized definition of what it means to be GPU bound. The term "GPU Bound" refers to when the performance (FPS) in a game or application (GPU task) does not change regardless of the processor and or memory used in the computer because the graphics card in question is the overall systems limiting factor. The statement is broad, which allows for the unattended misuse of the phrase. The complexity becomes more apparent when CPU clock frequency, number of CPU Cores, memory speeds, the total amount of memory available and application in question is combined.

The Breakdown

To break it down to get a better understanding, we can first take a look at the impact of just the CPU frequency on a given game, and how it changes the frame rate. Using the Intel i9 13900K and Forza Horizon 5 for this example, we can see that it is only when the CPU frequency is lowered to 3.7 GHz does it impact on the overall frame rate.


This next chart shows the impact on the average frame rate compared to the number of cores enabled. It is only when just 2 cores (4 threads) are enabled does the game frame rate become impacted, due to not enough resources for the windows background tasks. When enabling the E-Cores again, the frame rate returns to normal.


Now knowing that these E-cores are good at performing background tasks, we can once again disable them, leaving all P-cores enabled, and see how the P-Core CPU frequency impacts the game performance on their own.


With the data collected so far, the final test is to see how much of an impact does system memory have on Forza Horizon 5 once the CPU is the bottleneck. On the highest graphical preset, the average frame-rate impact is minimal. However, when switching to medium settings, the CPU bottleneck magnifies. Forza Horizon 5 is only one example of how system memory can influence a games frame-rate under the right circumstances.


The frame-rate limitation here is mainly the graphics card. This is an infinite cycle, a more powerful graphics card raises the frame-rate, which will surpass the current CPU abilities to compute the necessary game logic for each frame rendered. Games that are less optimized, have more world physics, and larger general compute sets per frame will need more CPU processing power. If the processor in question can also complete those tasks quicker with the aid of faster system memory, then RAM speed becomes a factor that influences FPS. Ultimately, it depends on the configuration of the computer, game resolution and graphical preset. If you find these tests interesting, try to replicate this breakdown of your favorite game and share your results on the TPU forums!

Why do I get different results?

Besides having different computer hardware, other factors play a role in the overall frame-rate. Details like the version of Windows you are using, current graphics drivers, game version and Windows power saving modes will change the outcome to a certain degree. Motherboard features like Resize-Bar or memory training algorithms can change the overall frame rate for games as well. The chart above is a example two motherboards using the same exact hardware, yet generate different average frame rates. Sometimes, things will just remain a mystery.