How do I fix Huntkey T620 stuttering in World War Z?

Loading maps felt like a slideshow. I tried a 32GB page file, but FPS dropped to 61. I used GamePP BIOS Wizard to set timings to 36-38-38-72 at 1.30V. AIDA64 showed latency dropping to 76-82ns. MemTest86 confirmed zero errors. This fix restored smooth gameplay.