Apple hyped Quartz Extreme, 3D acceleration on Mac OS X, quite a bit when Tiger was released. But they ship Mac OS X with 2D acceleration disabled. (Wha?)
Apparently on some hardware and with some software there are rendering glitches. On my Macbook Pro with all the software I use I haven’t seen any yet. And with it on, many applications, especially Firefox which does some ugly things with lots of 1x1px hidden windows, are several times faster than without the acceleration.
To turn it on temporarily, install the Developer Tools, launch QuartzDebug and enable it from the menu. You have to launch an app after it’s been enabled to get acceleration.
When you quit QuartzDebug it’ll be disabled again. To turn it on permanently (until you launch QuartzDebug again, anyway) execute this command:
sudo defaults write /Library/Preferences/com.apple.windowserver Quartz2DExtremeEnabled true
Once you’re satisfied that it works well, if you use an LCD display, try turning off BeamSync – a rendering delay built in to sync the screen refresh with the CRT electron beam sweep. You can test this in QuartzDebug or turn it off via the command line:
sudo defaults write /Library/Preferences/com.apple.windowserver Compositor -dict deferredUpdates 0
You can also edit these with PropertyListEditor, but you’ll have to give the admin group write access to it first:
sudo chmod 664 /Library/Preferences/com.apple.windowserver
Note, QuartzDebug resets this to 644 when you launch it.