Why does Expeditions: Rome crash during large legion battles?

I felt immense anxiety when the game crashed during a decisive charge, especially with this card's high factory overclock. I tried lowering the core frequency by 100MHz in the driver; while crashes decreased, the minimum FPS dropped from 45 to 38 per MSI Afterburner, which was a disappointing trade-off. I used the GamePP BIOS Load-Line Voltage Adjustment Wizard to lock VRAM voltage at 1.38V and switched to L2 mode. AIDA64 confirmed core temperatures stabilized at 65-72℃, and GPU-Z showed the voltage drop was minimized to 0.06V.