How to Manually Switch Graphics Cards on MacBook Pro
You can now keep track of which GPU is in use and then manually switch between the two graphics cards included within the MacBook Pro i5 and i7 series, all you need to do is download a utility called gfxCardStatus, which does this and more:
* Manually switch between the MacBook Pro GPU’s on demand through a menu bar application!
* gfxCardStatus tells you which card is currently in use by adjusting the menubar icon; showing an ‘i’ icon for the Intel HD GPU, and an ‘d’ icon for the discrete card, whether it’s an NVIDIA GeForce or an ATI or AMD card.
* Lists dependent processes to see which apps are currently using the discrete GPU processor.
The app is works with the all modern MacBook Pro’s and later with Core i5 or i7 processors.
You can get gfxCardStatus here for free, it’s donationware so if you’re thrilled with the app throw the developer a couple bucks.
This functionality really should have been baked into a system update for these MacBook Pro’s. Since the 330m is power hungry, if you want to preserve battery life you’ll almost certainly be better off using the Intel HD Graphics card instead. Note that the application is “a little bit on the buggy side” according to Engadget, and we’d recommend approaching anything that modifies your hardware settings with some caution.