How to stop FPS drops from 60 to 15 in Far Cry on ASRock H310CM?

While sneaking through the jungle, my stable 60 FPS would suddenly crash to 15, which was incredibly irritating. I tried lowering the memory frequency in BIOS, but it only raised the minimum FPS to 20 and lowered overall performance, leaving me worried. I used the GamePP BIOS Load-Line Voltage Adjustment Wizard to raise memory voltage to 1.35V per HWInfo and relaxed tRAS to 40. RTSS showed frame intervals converged to 10-16ms from 15-40ms, and AIDA64 confirmed temps at 43-47℃.