GA9Z — Gaming Performance Check | ga9z.net
Frame time converts directly to frame rate, and the 99th percentile of frame rates is what separates a smooth run from an average that flatters the hardware.
Frame time is the gap between frames in milliseconds, and the conversion is exact: divide 1000 ms by the frame time to get FPS. 16.7 ms equals 60 FPS, 11.1 ms equals 90 FPS, 6.9 ms equals 144 FPS and 4.2 ms equals 240 FPS. Reading frame time directly lets you spot a spike the average smooths over.
What each figure means in practice: 16.7 ms is the ceiling of a 60 Hz panel and the point VSync caps at; 11.1 ms is a comfortable margin above that ceiling; 6.9 ms is the budget a 144 Hz display needs to show every frame; 4.2 ms is what 240 FPS demands from the whole pipeline, CPU included.
On narrow screens, swipe or scroll the plate sideways.
The 99th percentile — the 1% low — is read as a frame rate, not as a time. Reviewers report it because a game may average 60 FPS and still look choppy on a poor frame time: the worst one percent of frames is what the eye registers as stutter, and the average does not contain them.
When to cap the frame rate near the 1% low: if your average sits far above your refresh rate but the 1% low dips below it, the cap buys consistent frame times and lower input lag instead of a headline FPS figure. VSync is the blunt version of the same idea — it caps the frame rate at the display refresh rate and raises input lag — while an in-game cap set a little above the 1% low keeps the pipeline fed without the added delay.
A run whose average and 1% low sit close together is a run whose frame times are even. A wide gap between the two numbers points at one of the failure modes of the measurement itself — a background recorder, a thermal throttle or scene-dependent loading — rather than at a steady hardware limit.
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