Days Gone has these annoying 0.5s freezes when switching maps on my Great Wall GW3300 2TB. How do I fix this?

Whenever I entered a large town, the screen would just freeze for about half a second. In a fight, that's enough to get you killed. The Great Wall GW3300 2TB was showing 12-18ms latency spikes on the PCIe link under load, leaving the CPU idling while waiting for data. I tried disabling all background update services, but that did absolutely nothing—a waste of time when the problem is this deep in the hardware. I went into the BIOS and forced the M.2 slot from 'Auto' to 'Gen 3' and updated the chipset drivers. In RivaTuner, the frame time spikes dropped from 45ms to a manageable 11-14ms. I did notice my old SATA drive started booting slower after forcing Gen 3, which I had to fix by rearranging the SATA port assignments on the board. Drive temps are around 50-56℃ with reads stable at 3200MB/s. After three hours of gameplay, no more freezes, and memory temps are sitting at 58-63℃.