The launch of the Ageia PhysX card at the Games Developer Conference in March caused major excitement because it added a new category of hardware to the world of PCs. We all like bigger, faster, cheaper versions of existing products but something that is genuinely new will send the Press into a feeding frenzy. For one thing itâ€™s interesting and for another you have to assess the device before you come to a conclusion about its merits, but mostly we love new technology because we get to know something that puts us ahead of the herd.
A dedicated PPU (Physics Processing Unit) on a PCI card that offloads physics from the CPU and GPU to speed up games and makes them look more realistic is exactly the sort of thing that piques our interest, even though none of us had heard of Ageia www.ageia.com until recently.
The PhysX card is now available for pre-order in the UK and the 128MB version from BFG costs Â£217 including VAT at Overclockers. Asus has the exclusive rights to the 256MB version and when it launches its PhysX card you can expect it to cost up to Â£249, which is the price of a GeForce 7900 GT graphics card or an Athlon 64 X2 4200+ processor, so weâ€™re talking about serious cash for a piece of hardware that presently has no function.
Ageia reasoned that some games are CPU limited, while others are GPU limited and that a product that could help to reduce bottlenecks could be a winner, in this case by handling the physics elements of a game. At a basic level this is simple to understand; hit a packing crate with your crowbar and it will break into a number of pieces so you can get at the contents. Fire a rocket into a door and it will explode into fragments, allowing you to pass into the next room. Shoot a bad guy with your shotgun and youâ€™ll blow a hole in his chest, killing him stone dead, but will the planks from the crate look realistic? Will the pieces of door that are left hanging in the frame obstruct your way? Will the corpse look like one of the cadavers that you see in CSI?
Well no, they wonâ€™t.
In part itâ€™s because the physics get complicated and in part because it doesnâ€™t really matter if the effects arenâ€™t entirely realistic but if a modern PC has the resources to deliver a game at high resolution with superb graphics quality and at a decent frame rate then naturally weâ€™ll want to see it, physics and all.
Thereâ€™s a huge divergence in views when it comes to the delivery of physical effects. nVidia has been trumpeting a tie-in with Havok which is called Havok FX. The idea is that you have one or more mighty graphics cards running inside your PC that have so much graphical power that one card â€“ or a part of a card - can be devoted to the physics of the game and the other one and a half (or whatever) is left to sort out the 3D action.