Why does Days Gone stutter violently when loading new map regions?

It's unbearable—while riding in Days Gone, loading new areas causes violent stutters where FPS drops from 70 to 20. I tried disabling unnecessary USB devices, but the drops still happened every 10-15 seconds, which was an infuriatingly inefficient attempt. GamePP Resource Scheduler showed PCIe channel conflicts with I/O wait times of 120ms. A reckless attempt to set virtual memory to 64GB actually worsened the lag. I finally set the game to 'Realtime' priority and limited background drivers. 3DMark stress tests showed frame time fluctuations converged from 15-50ms to 12-20ms, and AIDA64 confirmed CPU temps at 62-70℃.