Why does my Vastarmor RX 9070 XT experience frame rate drops during boss battles in Silksong?

Boss battles in Silksong caused frame rate fluctuations on my Vastarmor RX 9070 XT, which was frustrating. I tried manually adjusting fan speed, but the noise increased while the temp drop was minimal. I used the GamePP Fan Curve Configuration Panel to raise the fan speed at 75℃ to 2000 RPM and smoothed the curve slope. GamePP Hardware Sensors confirmed GPU temperature stabilized at 72-75℃ and fan speed at 2000-2200 RPM. I backed up the config to keep it.