Spotlight on the MacBook Pro’s improved graphics

The new MacBook Pros unveiled Tuesday may look identical to Apple’s previous batch of pro laptops, but there are a few notable under-the-hood upgrades. Chief among them are the new graphics found throughout the line that should make these MacBook Pros significantly faster at graphics-intensive tasks, while also increasing battery life.

The 13-inch models offer only integrated graphics, which share up to 256MB of main memory. This was also the case with the mid-2009 13-inch models. However, with this latest batch of MacBook Pros, Apple has replaced the Nvidia GeForce 9400M with the more powerful GeForce 320M, which has three times as many processing cores—48—as the 9400M. We haven’t been able to test these systems ourselves yet, but Apple claims that this new graphics processor can run up to 80 percent faster than the integrated graphics found in its previous batch of 13-inch laptops. Equally impressive is the company’s claim of increased energy efficiency, with the 320M using up to 40 percent less power than the 9400M. That should help allow the new 13-inch MacBook Pro to run for as long as 10 hours on a single battery charge, according to Apple’s figures on rated battery life.

All 15- and 17-inch MacBook Pros now offer both integrated and discrete graphics—previously, the entry-level 15-inch MacBook Pro had only integrated graphics. The new models use Intel HD integrated graphics for general-use applications, like iTunes, Mail, and Safari, but can automatically switch to the dedicated Nvidia GeForce GT330M graphics for tasks requiring more horsepower. Apple claims that the GeForce GT330M can run as much as twice as fast as the integrated GeForce 320M graphics found in the new 13-inch MacBook Pros. The new graphics in the 15- and 17inch models also use 30 percent less energy than their predecessors, helping the new those systems get up to between eight and nine hours of use from a single battery cycle.

New to these dual-graphics portables is an automatic switching technology developed by Apple. The technology looks for frameworks needed by individual apps at launch (such as OpenGL and Core Animation) to decide when to seamlessly switch from its energy-sipping integrated graphics to the higher-powered discrete graphics processor. Previously, a user had to decide which graphics to use, and switching between them required logging out and back into OS X.

Checking your e-mail, surfing the Web, or even watching 720p HD video in iTunes all work just fine using the integrated Intel HD graphics. Launch Aperture, however, and the MacBook Pro will automatically switch to the GeForce dedicated graphics for all of your work (that includes other apps you may have open along with the app that triggered the switch) until you quit the graphics-intensive app.

You no longer have (or are able) to decide whether to use lower power graphics to play a graphically demanding game like Call of Duty 4: Modern Warfare ( ). However, you can turn off automatic graphics switching—these new models include an Automatic Graphics Switching checkbox in the Energy Saver preference pane that’s selected by default. Turning it off forces the MacBook Pro into discrete graphics-only mode. (There’s no way to tell the computer to use only the integrated graphics system).

Though similar, Apple says its auto-switching technology is different than Nvidia’s Optimus graphics switching technology, which works on Windows systems and looks for calls from applications using DirectX or CUDA, for example, to trigger the switch. Optimus also uses application profiles to see whether the app requires or would benefit from using the discrete graphics. According to Nvidia’s Optimus whitepaper, the profiles live on Nvidia servers and are “automatically pushed to the end user,” though users can turn off these updates via the Nvidia Control Panel.

We’re just starting our initial Macworld Lab tests of these new MacBook Pros. Check back for Speedmark 6 results and our full review of all six new systems soon.

[James Galbraith is Macworld’s lab director.]