The GPU usage in games can vary based on several factors, including the game's graphics settings, the complexity of the scene being rendered, and other applications running in the background that are competing for GPU resources. In your case, it's possible that the GPU is being utilized more when the scene being rendered is more complex or when there are more in-game utilities being used. When the GPU usage is lower, it's likely that the scene being rendered is less complex or that fewer in-game utilities are being used.It's also possible that the game's graphics settings are causing the GPU usage to fluctuate. You may want to experiment with lowering or increasing the graphics settings to see if this affects GPU usage and FPS.
Another possible factor is the temperature of your GPU. If your GPU is running hot, it may throttle its performance to prevent overheating, which could explain the lower GPU usage and FPS. You may want to monitor the temperature of your GPU while gaming and ensure that it's within safe limits.
Overall, GPU usage can vary based on many different factors, and it's normal to see fluctuations in usage and FPS during gameplay. As long as your GPU is not overheating and your FPS is within an acceptable range, you shouldn't be too concerned.
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