PhysX By The Numbers
Mafia II's PhysX Benchmark
Mafia II includes a benchmark based on part of Chapter V: The Buzzsaw. The sequence matches real game play with one critical distinction. If PhysX is set to 'High', the benchmark generates far more debris than in the actual game.
In the test, a quick exchange of fire blows apart enough concrete and wood chips to build two new homes in a tropical island ghetto. In-game, it took repeated shotgun blasts at point-blank range to reproduce a similar amount of debris. This difference is unique to 'High' mode—if you run the test with PhysX set to 'Medium', the benchmark appears to mirror what's seen in game.
The 'High' version of the benchmark is a worst-case scenario that's doesn't represent the game as a whole. If you do hit a rough spot in one of the few PhysX-heavy areas, simply drop quality settings, play through the tough bit, and turn them back up.
At the end of a benchmark run Mafia II assigns a grade (A-F) to your system, but these ratings are of dubious value. According to the benchmark, our testbed scored a "D", but in-game framerates were substantially higher than our benchmark frame rates. Mafia II's benchmark is useful as a worst-case scenario, but we recommend you play through parts of the game before you settle on video settings.
Mafia II recommends an Intel Core i7-920 CPU and at least a GTX 260 with a dedicated 9800 GTX for PhysX at Medium and a GTX 470 + 9800 GTX for High. We tested the following GPU configurations:
- 1x GTX 480 (no dedicated PhysX GPU)
- 1x GTX 480 + 1x 9500 GT (512MB of RAM, dedicated PhysX GPU)
- 1x GTX 480 + 1x GTX 260 (896MB of RAM, dedicated PhysX GPU, 65nm, 192 cores)
We tested Mafia II on an Intel Kentsfield Q6600 @ 3GHz, a GeForce GTX 480, 4GB of RAM, and 32-bit Windows Vista. None of you are allowed to snicker since the testbed, in this instance, is the author's primary PC. We ran the benchmark test 3x in each case and averaged the results.
All graphics detail levels were turned to their highest levels, anisotropic filtering was set to 16x, antialiasing was enabled in-game (there's no selection option beyond On/Off), and vertical sync was off.
The GTX 480 slumps when we turn PhysX on; performance drops by 55 percent. Adding the 9500 GT actually slowed the game slightly, but improved Medium performance by eight percent. When we upgraded to a GTX 260, we saw a very different set of numbers. In both cases, using the GTX 260 for PhysX improved frame rates by 30 percent over the GTX 480 alone.
According to NVIDIA, the additional performance a dedicated PhysX card can provide is inversely proportional to the load placed on the primary GPU. The more eye candy the primary GPU has to deal with, in other words, the less difference a dedicated PhysX card can make. Adding the GTX 260 markedly improved framerates, but the value of that contribution depends on whether you have a spare NV GPU, your primary video card, and how much you care about PhysX.
Mafia II is good enough to be another feather in NVIDIA's hardware PhysX cap but it's not as good a game as Arkham Asylum. If you're curious as to why, flip the page and check our review.