Introduction

By now you’ve no doubt probably heard about AGEIA’s PhysX physics processing unit, first announced by AGEIA at GDC last year. PhysX has been hyped to change the way games are played, as physics processing could potentially be used to handle a wide range of effects, and we’re not just talking simple stuff like shooting a barrel to see a larger explosion or other geometry-based eye candy effects that have been handled by GPUs and CPUs up to this point. PhysX could eventually be used for tasks like fluid and cloth animation, eventually AGEIA envisions a future where the physics effects produced by their PhysX processor can affect gameplay elements, making a physics processing unit a requirement just as 3D accelerators are required for most of today’s latest games.

We’re still a long way off from that happening though. Because of this, rather than officially “review” the first wave of PhysX hardware from ASUS and BFG we’ve instead decided that we’re going to sum up the situation as it stands now in early May 2006. We’ll periodically revisit the topic from time to time as new, more significant developments occur. We feel this makes more sense than reviewing PhysX, as there’s only one game on the market that officially supports the technology at this point -- could you imagine reviewing the first Voodoo Graphics card based on the Glide-enhanced version of Tomb Raider, or the Radeon 9700 Pro based on the games of its era? With AGEIA claiming over 100 PhysX titles in the works from 60 different game developers, it’s way too soon to come to any final conclusions based on the experience delivered by one developer in one game. Instead what we’re going to do is discuss the important topics that have come up regarding PhysX, hopefully this article will answer some of the nagging questions that are out there regarding the technology and how it works as of right now. Let’s first start by discussing the hardware itself.

The ASUS and BFG PhysX cards

Looks like a graphics card until you see the backplate

The PhysX cards

Up to this point, AGEIA has signed on two board partners who are responsible for manufacturing PhysX cards, ASUS and BFG. While there are differences between the two boards, they’re both functionally the same – neither card is capable of rendering some effects that the other card can’t, nor is there a performance difference between either board.

ASUS made a splash with their announcement that their PhysX board would ship with 256MB of memory, twice the amount of memory than that found on the BFG card, but in actuality the PhysX processor can only address up to 128MB of memory, so the additional 128MB of memory on our pre-release ASUS PhysX board is left unused. As a result ASUS announced that all boards currently in production would be outfitted with 128MB of RAM rather than the 256MB on our card. Since the additional memory isn’t supported by the PhysX chip anyway, there should be no performance difference if you were an early adopter and happened to get a 256MB ASUS card.