- What is ghosting and what does overdrive do about it?
- Ghosting is a faint trail behind a moving object. Liquid crystals need time to twist from one brightness to another, and while they are still moving, the previous frame is partly visible. Overdrive pushes the pixel with a higher voltage than the target value so it gets there faster. Too little overdrive leaves the trail; too much causes the opposite problem, overshoot.
- What is inverse ghosting or overshoot?
- Overshoot is the panel going past the target brightness before settling, which shows as a bright or dark halo on the edge of a moving object rather than a smear behind it. It is a sign that the overdrive setting is too aggressive for the refresh rate in use. Many monitors have several overdrive levels in their menu; the ghosting pattern lets you compare them on the spot.
- Why does 144 Hz look smoother than 60 Hz?
- Two reasons. At 144 Hz the screen updates every 6.9 ms instead of every 16.7 ms, so a moving object is shown at more positions along its path and each step is smaller. And because each frame is held for less time, the image your eye tracks across the screen smears less, which is why text stays readable at higher speeds. The pixels-per-second readout makes this visible: the same pixels per frame is a much faster movement on a high refresh rate display.
- Can a browser test tearing at all?
- Only partly, and this page says so rather than pretending otherwise. A browser tab hands out one animation frame per display refresh and cannot disable vsync, so on most systems the bars will stay straight. Tearing still appears when the operating system or graphics driver lets the browser present frames out of sync with the display, for example with vsync forced off in the driver or with some compositor settings. If you see torn bars here, the display pipeline is tearing; if you do not, a game with vsync off can still tear.
- What do response time numbers mean and is 1 ms the whole story?
- Response time is how long a pixel takes to change from one grey level to another. The 1 ms on the box is usually the fastest single transition under the most aggressive overdrive, measured in a way the manufacturer chooses. Real transitions between similar greys are often several times slower, and the overdrive needed to reach 1 ms tends to cause the overshoot you can see in this test. What you see on the three bands matters more than the number on the box.