Opera 12 alpha arrived on October 13, 2011 with what Opera called a major technical milestone: full hardware acceleration with WebGL. It makes animations and graphics-heavy pages faster on a good graphics card. On an older card or a buggy driver, though, it can bring glitches, crashes or high CPU use. Here is how to turn both features off in Opera 12, and how to switch them back on.
What hardware acceleration does in Opera 12
Hardware acceleration moves graphics rendering from the processor (CPU) to the graphics card (GPU). It also makes WebGL possible, which lets developers build 3D games and demos that run in the browser. Opera’s approach is different from other browsers: it renders everything on the GPU when it can, including the whole user interface, the web page and WebGL content.
The alpha build only supported OpenGL. DirectX 9 and 10 support on Windows was still being worked on. Opera blocks graphics cards and drivers known to cause trouble, using blocklists stored in the extra folder inside the Opera install directory. A blocked card falls back to Opera’s software renderer.
Check your hardware acceleration status
Type opera:gpu in the address bar. If the page says “Vega backend Software”, Opera is not using your GPU. Opera suggests updating your graphics driver in that case. Some older cards are no longer supported by their makers and may stay blocked even with the latest driver.
How to disable hardware acceleration in Opera 12
- Type opera:config#UserPrefs|EnableHardwareAcceleration in the address bar and press Enter.
- Change the value to 0.
- Click Save, then restart Opera.
The preference takes three values: 0 = off, 1 = auto (the normal setting), 2 = force on.
How to disable WebGL in Opera 12
- Open opera:config#UserPrefs|EnableWebGL.
- Set it to 0 to turn WebGL off.
- Save and restart Opera.
The same values apply: 0 = off, 1 = auto, 2 = force on. Opera disables WebGL automatically on some cards because of card or driver problems. If you are confident yours works, you can set it to 2 to force it on, but Opera advises changing these settings only for testing.
Use it to track down rendering bugs
If a page draws wrongly or Opera crashes, set hardware acceleration to 0, restart and see whether the problem is still there. If it disappears, the GPU path is the cause. Remember to put the value back to 1 afterwards. Opera’s team asked testers who found such bugs to report the steps along with their operating system, graphics card model and driver version.
Turning it back on
Opera 12 final later shipped with these features switched off by default. To enable them again, set both preferences back to 1, as described in our guide to turning on hardware acceleration and WebGL in Opera 12.
Today
These opera:config switches belong to Opera 12, a browser that has long been retired. Current Opera versions are configured differently. If you want to turn WebGL off in another browser instead, see how to disable WebGL in Chrome.
