My ASRock Z370M Pro4 is causing wild FPS swings in Zenless Zone Zero combat, do I need to manually adjust the timings?

During fast combat swaps, the framerate was bouncing between 45 - 60 FPS, which felt really jittery on this aging board. The memory controller on the ASRock Z370M Pro4 was struggling with the new game's instruction sets, and the default XMP profile was throwing 3 - 5% checksum errors. I tried downclocking the RAM to 2666MHz; the swings stopped, but my 1% lows tanked from 35 to 28 FPS, which was a trade-off I couldn't live with. Instead, I went for a manual tightening strategy, moving the CL from 16 to 18 and bumping the voltage from 1.2V to 1.35V. Frame time monitoring showed the 1% lows jump from 22 to 38 FPS, making the game feel way more fluid. I did hit two random reboots after the voltage bump, but loosening tRAS by 4 units stabilized everything. RAM temps are 42 - 48℃ and the board core is at 55 - 62℃. MemTest86 passed 4 cycles with zero errors.