How to fix WD SN850 write latency stutters in Gears 5?
Switching between cover, I'd get these tiny frame skips that felt like a scratched DVD. Monitoring the background, I found that the WD SN850 1TB's write latency would spike from 0.1ms to 15ms during auto-saves, forcing the game engine to wait for I/O and causing frame time spikes. I tried moving the game to a different partition, but the hitches persisted—proving it was a controller scheduling issue. I went into Device Manager, disabled the write cache buffer flushing, and flashed the latest official firmware. RivaTuner showed the frame times tighten from a 12 - 35ms swing to a stable 11 - 14ms. I did lose about 2 seconds of boot time after disabling the cache, but enabling Fast Boot brought it back. Temps are a cool 42 - 48℃. A 3DMark storage benchmark confirms the random read/write latency is now at the floor. Everything is verified and rock steady.
