With hardware acceleration off, or a graphics driver the browser does not trust, the browser draws on the processor: video stutters, 3D pages crawl and the fans spin.
- Three signs say which is happening: the renderer the browser names, whether it refuses a context that must not fall back to software, and whether its WebGPU adapter calls itself a fallback.
- Chrome, Edge and Firefox each have a switch. Safari has none; it always draws with the graphics chip.
- When the switch is on and the check still fails, the browser has blocked the driver, and its own diagnostic page says why.
The short answer
Run the hardware acceleration test: it passes when the browser names a graphics chip and gives a hardware context. If it fails, turn the switch on for your browser, restart it, install the graphics driver from the chip or laptop maker, and run the check again.
The three signs
- The renderer. The WebGL renderer string, unmasked where the browser offers it. SwiftShader, llvmpipe, softpipe, Microsoft Basic Render Driver or Apple Software Renderer means the processor is drawing.
- The software-fallback probe. A second WebGL context asked for with failIfMajorPerformanceCaveat. A browser refuses it when it would draw in software, even where the renderer string does not say so.
- WebGPU. Whether the browser's WebGPU adapter, where it has one, reports itself as a fallback adapter that runs on the processor.
The switch, browser by browser
These are the same steps the test gives for the browser you run it in.
- Chrome: Settings, System, turn on Use graphics acceleration when available, then Relaunch. Other Chromium browsers keep the same switch under System.
- Edge: Settings, System and performance, turn on Use graphics acceleration when available, then Restart.
- Firefox: Settings, General, Performance, clear Use recommended performance settings and tick Use hardware acceleration when available, then restart Firefox.
- Safari: always draws with the graphics chip; there is no switch to turn on. Check that Low Power Mode is off and the system is up to date.
When the switch is already on
The browser can still block the graphics chip for a driver it does not trust or one that crashed. Install the driver from the chip maker (Intel, AMD, NVIDIA) or the laptop maker. Then open the browser's own diagnostic page: chrome://gpu in Chrome and other Chromium browsers, edge://gpu in Edge, about:support in Firefox. It lists each graphics feature as hardware accelerated, software only or disabled, with the reason.
On a laptop with two graphics chips, Windows chooses which one the browser gets: Settings, System, Display, Graphics, choose the browser, and set High performance. Then restart the browser.
Why it matters for the stress test
Every graphics stage of the SystemCheck stress test draws with WebGL 2. In software, those stages run on the processor and read far below the machine's real graphics speed, and the report says so rather than scoring the result as the graphics chip.
Terms used here
Questions
- Should hardware acceleration be on or off?
- On, for nearly everyone. Off makes the processor draw everything, which is slower and uses more power. Turn it off only to test whether a graphics driver is causing a crash, then update the driver and turn it back on.
- Does this check video decoding too?
- No. It reads the drawing path. Whether the browser decodes AV1, HEVC, VP9 or H.264 on the graphics chip is a separate question, which the video decode test answers.