I’m annoyed. I’ve had my lovely late-2009 MacBook Pro with the incredible dual graphics processors for a couple months and I had the slower GPU enabled the whole time.
Apparently, you need to go into “System Preferences” -> “Energy Saver” and turn on “Graphics” -> “Higher Performance”1.
I am annoyed, because I thought the problems with Sims 3 was because it was having trouble, not because I was using the slow GPU.
Even more annoying, I was (apparently falsely) under the impression that this switch was either obvious, easy or happened automagically when plugging or unplugging the power.
Well, hopefully some day this will be enabled. Meanwhile, I’m going to check to see if the GCD needs enabling too.
UPDATE: I found gfxCardStatus which allows you to see which video card is enabled. Unfortunately, the icons are weird for my laptop; I have two nVidia GPUs, but it was designed for ones that have an Intel and nVidia. But it works fine.
I edited an entire Final Cut Express movie and forgot I was still using the slower (sorry more efficient) GPU. And I knew how to change it!