There's no doubt that hardware will be required sooner orlater to make the increasingly complex physics simulations in future gamespossible. But right now, you can get by without it. So why is there another battle between Intel and AMD brewing over hardware physics?

Causing Havok

Just to fill you in with the background details, Intelannounced it was buying industry-leading gaming physics API developer Havok back in September.Now AMD is talking about acquiring AGEIA, presumably as a counter-attack.

But owning your own hardware physics engine is clearly nowherenear as essential as an in-house graphics division. The interest in physics islooking well into the future. Despite PhysX hardware arriving on the marketback in May 2006, there still aren't that many games around which support it.And many of those that do aren't that impressive.

Ghost Recon: Advanced Warfighter 2 and Unreal Tournament 3merely offer a bit more gore when you kill someone, and a bit more debrisflying off scenery when you shoot it. The result is a marginal amount of extrarealism, but no new dimensions to gameplay. A mod-kit with two special PhysXlevels has just been released for UT3,but hardware support is not essential for the rest of the levels.

Mind that box!

The game where PhysX is used to its utmost is CellFactor:Revolution. Here, destroying scenery becomes a strategic tactic, as you watchlarge falling objects crush your foes. The billowing curtains and clothing, andthe piles of boxes waiting to be kicked around, are a little more gratuitous.

However, if you don't have PhysX hardware acceleration,CellFactor: Revolution is virtually unplayable. So, as with any new technology,it's a proverbial Catch 22 situation. Games developers won't target PhysX untilenough people own it to make the trouble financially worthwhile, unless theyare paid to do so by the hardware company. And not that many of us will buyPhysX cards until enough games supporting them arrive.

Something similar has happened with Creative's X-RAMtechnology. This is the extra memory on premium Creative X-Fi cards, which canbe used to increase performance with higher-resolution audio effects. Even now,not that many games support it, and it's far from essential. Since most gamesare developed for consoles first due to the much larger market, then ported tothe PC, the demand for support isn't that great.

Nevertheless, PCs are arriving with PhysX on board - evennotebooks. Dell's Inspiron XPS M1730 is the first portable to ship with AGEIA'sPhysX 100M, which is a standard feature across the range of options. It hasalso become a tickbox with customised enthusiast desktops, helped by the factthat the BFG PhysX card is now under £100.

Clash of the physicstitans

Intel's purchase of Havok looks like it has put paid to arather interesting bit of sideline business which was brewing for graphicschips. HavokFX was going to be run on Nvidia and ATI graphics hardware,harnessing the immense calculation power of GPUs with a unified shaderarchitecture for tasks other than real-time 3D rendering. With Havok the marketleader in games physics, the appeal of this approach looked much wider than forAGEIA's PhysX.

However, Sony licensed the PhysX SDK for the Playstation 3back in 2005, as it can potentially run very well on the Cell processor's SPEs.And, as I've just argued, console support is the Holy Grail of any gaminghardware technology. Once you have that, game support will come - and thetechnology will become essential for PC gamers too.

So, assuming AMD can afford to buy AGEIA (which isquestionable in itself), gaming physics looks like it will be divided into twocamps. In the blue corner, the financial might of Intel and wide support ofHavok. And in the green/red corner (would that make brown?) will be AMD'sPhysX, with the backing of Sony's Playstation 3. Fortunately, you won't have topick sides just yet.