Sacred 2: Fallen Angel

Sacred 2 is billed as an "action RPG" in the vein of Diablo II, but it has much prettier graphics. The game's developers have raised the ante even further by adding some effects courtesy of Nvidia's PhysX technology, which enables GPU-accelerated physics on recent GeForce GPUs. PhysX uses the shader processors to handle mathematical simulations of things like collisions, fluid flow, and realistic cloth.

I don't believe there's anything inherent in the architecture of current Radeon GPUs that would prevent them from being similarly effective at processing physics routines. In fact, AMD has demonstrated GPU-accelerated physics using a combination of the OpenCL GPU-compute API and Havok middleware. But Nvidia owns PhysX and has elected not to extend support for GPU acceleration to third parties.

Like most games that use hardware-accelerated PhysX, the effects in Sacred 2 don't involve actual physical interactions in a way that affects the outcome of the game. They just enhance its look—not a bad contribution from a graphics card, if you think about it.

With PhysX, leaves swirl about the landscape, blowing in the wind

No PhysX, no leaves

In Sacred 2, turning on PhysX effects (via an option in a game menu) is mostly about leaves and other bits flying around on the screen. Without PhysX, the game looks great and seems fairly normal. With PhysX, you get lots and lots of leaves swirling about everywhere, especially when you cast a spell. I'd say the additional smithereens kicking about are an improvement overall, but they are probably overdone. Developers: just because you can doesn't mean you should. Sometimes, less is more.

We tested Sacred 2 at 1680x1050 resolution using its "high" quality presets along with 2X antialiasing. I chose 2X AA because going up to 4X seems to exact a big frame-rate hit. As a result, I found myself playing this game (for way too many hours) at 2X AA for the best combination of image quality and performance, even when I wasn't testing.

Without PhysX, the 4770 runs Sacred 2 faster than the 9800 GT does. To me, the 4770 runs the game fluidly at these settings, while the 9800 GT feels a little sluggish from time to time.

With PhysX enabled, the 9800 GT's frame rates drop quite a bit. You might have to compromise on antialiasing or dial back some other in-game quality settings to offset the hit. Then again, I tried turning on PhysX effects with the Radeon HD 4770, where the CPU has to do all of the work, and the performance hit there was brutal—we were into the 3-4 FPS range, too slow to play at all.