Portal 2 Performance: Mac vs PC

I won’t tread into the Mac versus PC debate since that’s a tired argument, since Windows is the clear winner in terms of game selection and performance, and since, ultimately, platform is a matter of preference. But for the sake of observation I ran several timedemos last night within the esteemed Portal 2, which, for that one person who doesn’t know, is a Steam Play app, meaning that a single purchase allows one to run Portal 2 on both his Windows and OS X machines.

The results are in Window’s favor.

The Setup

My test machine was a 2008 iMac (iMac 7,1 for those who care) laden with a 2.8 GHz Intel Core 2 Duo, 4GBs of 667Mhz DDR2 SDRAM, and an ATI Radeon HD2600 with 256MBs of VRAM.

For the test I ran Portal 2 under OS X 10.6.7 and Windows 7 Professional 64-bit. The latter, of course, was made viable through Boot Camp 3.2.

Both versions of the game were up-to-date, but I noticed that my OS X version read “May 5 2011 (4562)” whereas my Windows version read “May 3 2011 (4560).”

Neither OS was a fresh install, and so I killed as many running applications as I could to minimize outside influence. For testing consistency, I used the following in-game settings, changing the resolution with each test. There was one notable exception at the end.

• Aspect Ration 16:10
• Resolution See below charts
• Display Mode Full Screen
• Laptop Power Savings Disabled
• Anti-Aliasing Mode None
• Filtering Mode Anisotropic 2x
• Wait for Vertical Sync Disabled
• Multicore Rendering Enabled
• Shader Detail Medium
• Effect Detail Medium
• Model/Texture Detail Medium
• Paged Pool Memory Available High

The notable exception is Paged Pool Memory, a setting only available under the Windows version of Portal 2. Portal 2’s in-game tip says that Paged Pool Memory is used for the CPU. As far as I can tell, it probably helps pre-load textures into my system’s RAM.

The Results

Each chart represents a specific puzzle. Each data group represents either OS X or Windows running a specific resolution. The bars in each group represent three separate runs I performed under the given circumstances. The fourth bar represents that group’s average. For readability I included the numerical value of that average.

Across the board, Windows wins hands down.

On average my install of Windows 7 performed 34% better than OS X when running Portal 2 at 1920×1200. The difference was 33.5% at 1280×800.

I also ran Portal 2 in OS X at 1024×640 in attempt to match how Windows ran at 1280×800. While not spot on, the results were fairly comparable.

My Reaction

I suppose the most obvious response is outrage, a call for equality, or some fading words of self-deprecation. But to be honest, I approach all this with cold observation: it’s just a series of numbers within the torrent of what’s already common knowledge.

I played through Portal 2 in OS X, having recently installed its Windows counterpart to run this test. Like its predecessor, Portal 2 is memorable. I’m not as upset having experienced it at a somewhat graphical disadvantage as one should be having never experienced the game at all. Besides, to a large degree, this imbalance only gains relevance when I’m outside the game itself. Within Portal I am lost in its play, narrative, and the pursuit of cognizant gratification. I am unabashedly ignorant of these less-than-perfect touches when immersion takes over.

I guess that qualifies as self-aggrandizement.