Why Does Screen Tearing Happen and How Does Adaptive Sync Help Fix It

Quick Answer

Screen tearing happens when your GPU sends a new frame mid-scan, before the monitor finishes drawing the previous one, causing two partial frames to appear on screen at once as a visible horizontal split. Adaptive sync fixes it by making the monitor wait for the GPU's frame to complete before starting a new scan, synchronising the two devices in real time without the lag penalty of VSync.

Why Tearing Happens at the Hardware Level 🔧

Your GPU renders frames as fast as it can, independently of your monitor's fixed refresh cycle. A 75Hz monitor redraws the panel 75 times per second at regular intervals. If the GPU delivers its 80th rendered frame halfway through the monitor's 4th scan, the display draws the top half from the old frame and the bottom half from the new frame simultaneously, creating a horizontal cut across the image. This is most visible during fast horizontal panning in racing games and shooters. The faster the GPU relative to the monitor's refresh, the more frequent the tears, which is why a powerful RTX 4070 on a 60Hz or 75Hz display shows tearing more often than a weaker GPU on the same monitor.

How Adaptive Sync Eliminates Tearing 📡

Adaptive sync protocols, including FreeSync (AMD), G-Sync (Nvidia), and the open VESA Adaptive Sync standard, move control of the monitor's refresh timing to the GPU. Instead of scanning at a fixed interval, the monitor holds the current frame on screen until the GPU signals that the next frame is complete, then immediately scans the new frame. This eliminates the mid-scan frame delivery that causes tearing. The result is tear-free output without VSync's fixed-cap stutter. FreeSync Premium on monitors currently stocked at Evetech covers a typical range of 48Hz to 144Hz or 48Hz to 165Hz, which handles the full range of real-world frame delivery speeds.

VSync vs Adaptive Sync: The Trade-Offs 🎮

VSync prevents tearing by capping your GPU's frame delivery to the monitor's fixed refresh, but when your GPU drops even one frame below that cap, VSync introduces a full-frame stutter as the display repeats the previous frame. Adaptive sync has no fixed cap: it dynamically matches the monitor's refresh to wherever your GPU is actually running, whether 55 fps or 138 fps, delivering a smooth result without stutter. For South African gamers on connections with variable network latency, the in-game frame rate variation that comes from server-side micro-stutters is managed far better by adaptive sync than by VSync.

FAQ

Does adaptive sync work with all games?

Yes, adaptive sync operates at the display driver level and is game-agnostic. Any GPU rendering any application benefits from adaptive sync as long as the frame rate falls within the monitor's stated sync range, typically 48Hz to the panel's maximum refresh.

My game has VSync in its settings and my monitor has FreeSync. Which should I use?

Disable in-game VSync and use FreeSync via your GPU control panel and monitor OSD. Running both simultaneously can cause conflicts, including a halved effective frame rate on some systems.

Can adaptive sync reduce input lag compared to VSync?

Yes. VSync adds roughly half a frame of input lag to prevent tearing. Adaptive sync adds no fixed latency. For competitive play, adaptive sync with VSync disabled delivers both tear-free output and lower input lag simultaneously.