Ageia’s PhysX physics processing unit

I‘VE HAD THE CHANCE to spend a few days playing with a PhysX card from Ageia, and there is much to tell, though not much one can do with the hardware just yet. I did find some interesting ways to test the PhysX card, and the results may enlighten us about the prospects for physics acceleration in custom hardware. Read on to get my take on Ageia’s new physics processing unit.

The hardware
The PhysX card itself looks an awful lot like a video card, with its centrally located cooler and four-pin Molex aux-power connector, but don’t be fooled. This card’s metal slot cover is devoid of outputs, and the golden fingers extending from the board are intended to slip into a humble 32-bit PCI slot. This card is made for crunching numbers, not driving a display.

A pair of Ageia partners, Asus and BFG Tech, have brought PhysX cards to market. The board you see above is the BFG Tech version, and it comes with 128MB of Samsung GDDR3 memory chips attached. These chips run at an effective data rate of 733MHz on a 128-bit interface, which works out to 12 GB/s of memory bandwidth dedicated solely to physics processing.

Pop the cooler off of the card, and you’ll find the star of the show, the PhysX chip, residing below.

This custom-designed physics processor measures roughly 14 mm by 14 mm, or 196 mm2. TSMC packs about 125 million transistors into this space when it fabricates the chip using its 130 nm manufacturing process.

The itty little rectangular chip you see situated below the PhysX PPU, by the way, is not a bridge chip like you might see on some PCI cards these days. This chip comes from Texas Instruments and is used to step down the voltage coming in from the PCI bus. As a low-voltage 130 nm device, the PPU probably needs its assistance in talking to the relatively high-voltage PCI bus.

 

Ageia aims for physics coprocessing
Since Ageia first started making noise about accelerating gaming physics calculations in hardware, folks have been raising questions about whether such a thing makes sense. The acceleration of specific, particularly intensive computing problems using custom hardware can be a very potent thing, as the rise of custom graphics hardware in the past decade has demonstrated. CPUs are good at many things, but offloading certain jobs to custom hardware is often faster, more energy efficient, and enables more consistent performance. We now have custom chips or logic units to handle a host of specific tasks inside of a PC, including audio processing, video scaling and playback, and various types of I/O.

At first blush, physics seems like a pretty good candidate for hardware acceleration. Physics involves lots of floating-point math calculations that can potentially be processed in parallel. In games, physics processing must be fast in order to be useful; all calculations need to happen in real time, with updates coming each time the screen is redrawn. Much like graphics, physics is the sort of computing problem at which coprocessors can excel. Not only does that fact open the door for a custom physics processor, but the parallel nature of the task could help turn physics acceleration into a solid long-term chip business. The number of transistors possible on a chip should double every couple of years for as long as Moore’s Law holds out, and Ageia should be able to build ever more powerful physics processors as a result.

Sounds easy, right? Not exactly, but Ageia has taken on the twin challenges of building a custom physics processor and cultivating a healthy market for such a chip.

On the hardware end of things, the PhysX PPU is a bit of a mystery. Aside from transistor counts and the like, we know surprisingly little about it. The PPU has “many copies” of Ageia’s physics processing core onboard, but we don’t know exactly how many. Ageia is also coy about the clock speed of the PPU. Apparently they don’t want to give away the ingredients for the special sauce this early into the game. Without this information, we can’t come up with theoretical peak gigaFLOPs numbers or the like, for whatever they’re worth.

We do know a few things, though, and can speculate on some others. We know the SIMD exection cores must be geared to handle floating-point datatypes, for instance, and SIMD execution is probably narrower than on a graphics chip. Processing physics involves lots of interactions between different objects, and managing those interactions would require robust communication between the different execution cores on the chip—probably via an internal switched fabric. Ageia claims the PhysX PPU has “two terabits per second”—or about 250 GB/s—of bidirectional memory bandwidth internally.

On the software front, Ageia has its PhysX API that game developers can use to access a range of physics capabilities. When we think of gaming physics, the first thing that comes to mind is typically rigid-body interactions—a grenade bouncing around a corner, a race car running into a wall, etc—but rigid bodies are just part of the picture. Ageia’s software can also handle particles (for smoke, dust, etc.), fluids, hair, cloth and clothing. Virtual joints and springs give “rag doll” characters and vehicles the appropriate flexibility and resistance, and materials can be programmed with specific properties—so that ice is slick, for instance. The PhysX software also supports collision detection for each type of object, so that different types of objects can interact realistically.

Most of these effects are familiar to gamers by now, but the distinctive thing about PhysX is that the PPU can accelerate these things in hardware. The PPU is programmable, and Ageia has chosen a subset of commonly used, performance-critical functions in the PhysX API to hand off to hardware. Over time, Ageia plans to accelerate more and more of the API’s capabilities via the PPU. In the absence of PPU hardware, the PhysX API will fall back to software processing. In fact, the PhysX software is multithreaded in order to take advantage of multi-core CPUs.

This software fallback is key to Ageia’s world domination plans. The company is licensing its entire PhysX API and software development kit, complete with tools, to PC game developers free of charge. The only catch: those games must take advantage of a PhysX PPU if present. Ageia has also shepherded the PhysX API’s migration on to next-gen game consoles. On the Xbox 360, game development houses can license the SDK for about $50,000, and it will use all three of the cores on the Xbox 360 CPU. Sony simply bought out the rights to the PhysX SDK for the PlayStation 3 so all developers can use it for free, and Sony engineers have ported the physics processing routines to the Cell processor. These efforts have made the PhysX API a reasonably complete, low-cost, cross-platform physics engine, and Ageia has had some success persuading game developers, game engine companies, and tool makers to use it.

The list of upcoming PhysX-fortified titles is long, but easily most prominent among them are Unreal Engine 3 and Unreal Tournament 2007. Unfortunately, the list of current titles with PhysX support is depressingly short. We’ll test the card with a couple of the most prominent titles shortly.

 

Ageia’s many challenges
Since their first press release hit the wire, naysayers have been predicting Ageia’s failure—and with good reason. You may have gathered by now that Ageia is attempting to do something fundamentally difficult. They face a number of challenges, including the chicken-and-egg problem involving a dearth of PhysX support in games and the lack of an installed base of PPU hardware. I must admit that I don’t have much of a taste for all of the triumphalist doomsaying we’ve been hearing. As a PC enthusiast, I love the idea of realistic physics simulations in games, and I’m generally favorably inclined toward new types of custom chips to make it happen. One would hope the PC gaming market would attract efforts like this one and reward them if they succeed.

That said, Ageia’s prospects are undeniably cloudy. We’ve already talked about how Ageia is addressing the software development question, but we should probably consider some other dark clouds on the horizon, as well. Among them:

Physics is not graphics. Everyone loves to use the analogy of GPUs when thinking about the development of physics acceleration. It’s almost inescapable. That analogy is sometimes helpful but fundamentally flawed, kind of like the car analogies that have plagued CPU performance discussions since the dawn of time (or the 1970s, whichever came first.) There are many ways in which physics and graphics are different, but the one that matters most, I think, has to do with the way physics support can be incorporated into games.

Old-timers like me remember when the first 3D graphics cards arrived. We were able to pop in a 3dfx Voodoo card or the like and get better graphics almost instantly thanks to modified versions of existing games, like GLQuake. The image quality was higher than software acceleration, and we could run games at higher display resolutions, too. This instant gratification sparked a wave of upgrades and helped 3dfx become a household name in a matter of months. Physics, however, has no easy analog to higher display resolutions and better quality texture filtering. Gamers can’t grab a PhysX card and expect an instant payoff. We’ll have to wait for games to catch up, and that could literally take years.

Eye candy isn’t interactivity. When PhysX support does arrive in games, it will likely take the form of improved visual effects, as it does today in Ghost Recon Advanced Warfighter. When you blow stuff up, the smithereens are legion. Bits and pieces of things are flying everywhere. But none of it affects gameplay in any meaningful way, because the game’s physical world wasn’t designed with hardware-accelerated physics in mind. Nifty visual effects present lots of opportunities to game developers, but if that PhysX card is going to be worth my money, I want to feel the impact of physics acceleration. Getting game developers to change their assumptions and really take advantage of physics hardware in ways that alter gameplay will probably be extremely tough, especially since, one would presume, the software-based fallback will be much slower. Playing the same game on a non-PPU-equipped system would have to be a different experience, with fewer physical objects onscreen and fewer possibilities for interaction.

There’s no killer app. This one flows from the last two and is very simple. I’m not the first one to say it, either. The PhysX PPU needs at least one really good game to demonstrate its power and really sell people on the concept. So far, it’s not here, and I’m not even sure a strong contender for this role is imminent.

The GPU/MPU challenge. ATI and NVIDIA have already teamed up with Ageia’s rival in the physics middleware market, Havok, to get preliminary demos of a GPU-accelerated physics API up and running. The graphics guys are talking big about the number of FLOPS they can bring to physics processing and are hungry to prove GPUs can do more than push pixels. The GPU-accelerated physics API, Havok FX, is currently an eye-candy-only affair, so game-critical physics simulations must still happen on the CPU. Still, if dedicating a second or third (or fifth) graphics card to physics can achieve results similar to Ageia’s in the short term, Ageia’s life could get complicated.

On top of that, execution cores in microprocessors are multiplying like rabbits these days, with two cores set to begin giving way to four by this time next year. I’m convinced that a custom chip designed for physics could theoretically outdo a multi-core CPU and probably a GPU in terms of peak physics processing capabilities, and Ageia talks a lot about the joys of custom chips when this topic comes up. Best to leave the graphics to the GPU and the game AI to the CPU, they say. What they haven’t convinced me, however, is that a multi-core CPU or a GPU—not to mention the combination of the two—isn’t sufficient to deliver in-game physics that are incredibly realistic and compelling.

Of course, just above we were fretting that the gap between the PPU haves and have-nots might be too large, so who the heck knows?

Is PCI the short bus to physics? I mention this one because we have a few folks in our news comments who persistently mention it as a show-stopping problem. Right now, PhysX cards will only plug into a PCI slot, and ye olde PCI is known for being relatively slow. No doubt Ageia chose PCI for cogent reasons, like the fact that they started development long ago, when PCI-E was but a gleam in Intel’s eye, or that they want to sell lots of cards as upgrades for existing PCs. Still, Ageia does have plans for a PCI Express version of the PhysX card at some point in the future.

Some folks seem to think PCI is impossibly slow for a really solid PPU implementation. I’ve asked Ageia about this issue repeatedly, they insist using PCI is really not a problem. Given the fact that the cards have 128MB of fast local memory, I’m mostly inclined to believe them. Of course, we won’t really know until we have games that really stress a PhysX card’s capabilities.

Is there room in the market? So you drink Bawls soda by the gallon and split your free time between Counter-Strike tournament play, trying out the latest game demos, and mastering the nuances of Oblivion. On the side, you’ve developed an entire alternate personality in WoW. You want to prove your bona-fides by building yourself the ultimate gaming rig, but your you’re on a generous-but-strict $1200 budget. How do you choose between paying more for a dual-core CPU, ponying up for a discrete sound card, abusing the plastic for a second video card, adding a drive for RAID 0, or going for that gorgeous new 20″ LCD? Wait, now you’re supposed buy a separate card for physics, too? For almost $300?!

Even if PhysX is worthy, Ageia may find it difficult to prosper in a PC market crowded with other pricey, enthusiast-oriented goodies.

I suppose I could dream up some more potential problems for Ageia, but that about covers the major ones. I think one really good killer app that illustrates compelling potential for PhysX could cut through most of these clouds like a bolt of sunlight, but it’s not here yet.

Since we’re a PC hardware review site, I’m bound by law and social contract to test the PhysX card and make some graphs. That portion of the review follows.

 

Our testing methods
As ever, we did our best to deliver clean benchmark numbers. Tests were run at least three times, and the results were averaged.

Our test system was configured like so:

Processor Athlon 64 X2 4800+ 2.4GHz
System bus 1GHz HyperTransport
Motherboard Asus A8R32-MVP Deluxe
BIOS revision 0404
North bridge Radeon Xpress 3200
South bridge ULi M1575
Chipset drivers ULi Integrated 2.20
Memory size 2GB (2 DIMMs)
Memory type Corsair CMX1024-4400 Pro
DDR SDRAM
at 400 MHz
CAS latency (CL) 2.5
RAS to CAS delay (tRCD) 3
RAS precharge (tRP) 3
Cycle time (tRAS) 8
Hard drive Maxtor DiamondMax 10 250GB SATA 150
Audio Integrated M1575/ALC880 with Realtek 5.10.00.5247 drivers
Graphics ATI Radeon X1900 XTX 512MB with Catalyst 6.5 drivers
Physics BFG Tech PhysX 128MB PCI with 2.4.3 FC1 drivers
OS Windows XP Professional (32-bit)
OS updates Service Pack 2, DirectX 9.0c update (April 2006)

Thanks to Corsair for providing us with memory for our testing. Although these particular modules are rated for CAS 3 at 400MHz, they ran perfectly for us with 2.5-3-3-8 timings at 2.85V.

Our test systems were powered by OCZ GameXStream 700W power supply units. Thanks to OCZ for providing these units for our use in testing.

Unless otherwise specified, image quality settings for the graphics cards were left at the control panel defaults.

The test systems’ Windows desktops were set at 1280×1024 in 32-bit color at an 85Hz screen refresh rate. Vertical refresh sync (vsync) was disabled for all tests.

We used the following versions of our test applications:

The tests and methods we employ are generally publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.

 

Ghost Recon Advanced Warfighter
GRAW is the first big game title with PhysX support, and Ageia chose to delay the launch of the first retail PhysX cards until its release. We’ve already covered the brouhaha that erupted when Havok announced that most of GRAW’s physics are done with Havok software, so we won’t rehash that one. The developers of the PC version of GRAW added extra physics-based eye candy using Ageia’s API and hardware. Here’s how it looks.


Without PhysX


With PhysX


Without PhysX


With PhysX


Without PhysX


With PhysX

Explosions like these are one of the few places in GRAW where PhysX effects are apparent. In the first frame, an almost supernatural amount of debris comes flying out of the exploded bus terminals (or phone booths or whatever.) The volume of junk flying through the air seems a little over the top to me, personally. The effects are more believable in frames two and three, and you can see how much more debris is scattered around on the ground in the third frame with PhysX.

Notice that the volume of smoke in frame three doesn’t seem to change when a PhysX card is added. These particle effects may be accelerated by the PhysX card, but it’s not apparent.

….aaand, that’s about it, really. GRAW isn’t much of a showcase for PhysX, and having seen it, I don’t think I’ve seen much of anything that wouldn’t be possible in software alone.

PhysX effects may be rare in GRAW, but we can measure performance when they’re present. I used FRAPS to capture frame rates during a 20-second sequence where I blew up some bus terminals and a jeep—the same scenes depicted in the GRAW screenshots above. I played through the sequence the same each time, and we averaged the results from five runs. In order to diminish the effect of outliers, we’ve reported the median of the five low frame rates we encountered.

In spite the fact that we used newer versions of the PhysX drivers and GRAW than most sites did during the initial wave of PhysX reviews, we still see performance degraded with PhysX enabled. This is an extreme example because we’re only testing a worst-case scenario where lots of physics effects are present, but this sort of scene is where PhysX is supposed to shine. Sadly, that’s not what happens.

 
CellFactor
GRAW may not be much of a showcase for PhysX, but the CellFactor demo is much more exciting. This first-person shooter-style demo was commissioned by Ageia to show off the PPU’s abilities, and it has more objects bouncing around onscreen and interacting with one another than any other game I can recall. We’re talking more rigid bodies than a three-story morgue. Not only can you blow up an unprecedented number of standard-issue FPS pipes, crates, and barrels, but the players also have Star Wars “force”-style telekinetic powers. Part of the fun is sending a pile of junk careening off of a platform and raining death on the unsuspecting players below. PhysX may not have a killer app yet, but playing this demo, you’ll definitely catch a glimpse of Ageia’s vision.

Being the nosy sort, I wanted to find a way to benchmark this app with and without a PhysX card, but Ageia said it would only run on PhysX hardware. I thought I was out of luck until I saw a post in our forms describing how to get CellFactor running without a PhysX card. I tried it, and lo and behold, it worked! CellFactor would start and run, and for the most part, it was intact. The huge numbers of objects onscreen remained, and performance was pretty snappy on our Athlon 64 X2-based test system. The only things missing were the occasional cloth and fluid effects, used sparingly in the demo level to simulate a giant banner, some radioactive goo, and (of course) blood.

Here’s a quick look at what was missing and what wasn’t.


With PhysX


Without PhysX


With PhysX


Without PhysX


With PhysX


Without PhysX

The pipes and other objects bounce around in the software mode the same as ever, but Ageia’s very realistic tearable cloth is completely missing.

 
CellFactor


With PhysX


Without PhysX


With PhysX


Without PhysX

Fluids are also missing in CellFactor’s software mode, but particle volumes look to be the same as with the PhysX card.

Obviously, disabling some of the effects means the software mode is less physics-intensive than CellFactor is with PhysX hardware. Still, the basic CellFactor gameplay is intact in software mode, complete with telekinetic powers and flying crates galore. The software-only version ran so well, I couldn’t help but try some benchmarking to see how it compared to the PhysX card.

 
CellFactor
I tested frame rates using FRAPS over the course of a 20-second sequence in which I blew stuff up with grenades. This test was about rigid bodies, and large numbers of ’em were onscreen during this sequence. No liquids were present onscreen during this test, and no cloth except for a few strips way in the background, and those were typically not affected by the action. As with GRAW, I tried to play through the scene the same way each time, and the results you see below are the average and median scores from five runs.

CellFactor appears to be capped at 45 FPS, by the way. The cap will no doubt keep average frame rates down.

The CPUs used to obtain the results below were all Athlon 64s with 1MB of L2 cache per core running at the speeds specified. (The 2.4GHz dual-core chip was an Athlon 64 X2 4800+, and the 2.8GHz one was an overclocked FX-62. The single-core 2.4GHz chip was an underclocked FX-57.) CellFactor was running with its default low-quality graphics settings.

The performance delta between the single-core CPU with and without PhysX is substantial, but that difference shrinks pretty dramatically when we add a second CPU core to the mix. Shockingly, the system with a 2.8GHz dual-core processor performs almost identically to the dual-core 2.4GHz system with a PhysX card.

Testing PhysX performance in this way may be mostly bogus, but these aren’t the sort of results Ageia wants to see, no doubt. In fact, Ageia seems to have been tracking various forum discussions about CellFactor software mode performance, and they’ve taken several steps to address the question.

First, they released a new version of the CellFactor demo with some changes. In the new version, cloth is enabled in software mode, despite the fact that it causes major visual artifacts and brings frame rates to a near standstill. Ageia also claims rigid-body performance and explosions are faster with this new version of Cell Factor. For what it’s worth, I tried the new R36 release of CellFactor with a PhysX card in our benchmarking sequence, and performance was essentially unchanged.

Second, Ageia’s release notes for CellFactor R36 now have a section titled “Framerate Numbers” that says the following:

It should be noted that the use of software frame grabber applications like FRAPS, even just to display FPS numbers, can slow down the game by up to 10 FPS or more, depending on the system and its settings. Due to this significant performance impact, software like this is not an accurate representation of overall game performance.

Hmm. Denigrating a particular testing method when you don’t like the results is a time-honored tradition in high-tech PR, but generally FRAPS has been one of the good guys in such debates, with 3DMark and timedemo functions getting the brunt of it. Now, the tables have turned. My, how times change!

I tried to test the impact of FRAPS on CellFactor frame rates in a very straightforward way. The CellFactor demo itself includes a metrics overlay, which you can see in my screenshots. I ran the demo with and without FRAPS and watched the demo’s built-in frame rate counter to see if things ran slower. From what I could see, FRAPS has no noticeable impact on frame rates.

Ageia has also tackled the CellFactor software mode issue by publishing an interview with the demo’s developer. The developer talks down rigid-body objects and collisions as “simple” and talks up cloth and fluids as the truly unique features in CellFactor. Here’s one key question and answer:

AGEIA: So you mentioned a “software mode” – is it possible to run CellFactor without hardware? If so, how does it run?

JS: Only if you want to miss out on a lot of what makes the game fun! I read on a forum somewhere that a player had done a command line switch and disabled support for the PhysX card. Of course he benchmarked it and it came back with a decent result. The reason for that is pretty simple – we never really intended for players to actually play the game like that, so we stripped the more advanced features out of the software mode (such as fluid and cloth); let’s not forget that AGIEA makes a very powerful physics software engine as well, so doing rigid body collisions (where boxes get tossed around) isn’t too much for the highest-end CPU’s to handle. With that said, in software mode, you’ll still notice a significant slow-down at moments of peak physics interaction on even the latest and greatest multi-core machines. That’s why we have the PhysX card listed as a requirement.

It’s good to see that Ageia’s PR folks are on the ball when it comes to this sensitive issue, but embedded in that answer—and in our CellFactor software benchmark results—is a noteworthy and inescapable truth: even the very large numbers of rigid-body collisions we see in CellFactor can be handled pretty well on a high-end, dual-core processor. The same would appear to be true for the particle effects we’ve seen in CellFactor and GRAW.

 

Power consumption
We measured total system power consumption at the wall socket using a watt meter. We plugged the monitor into a separate outlet, so its power draw was not part of our measurement. Also, we turned on the Athlon 64 X2’s Cool’n’Quiet clock throttling function for the idle tests at the Windows desktop, but disabled CnQ for the “load” tests. In order to make sure the PPU got a good workout, we took the power draw measurements under load with the system running the Cell Factor demo in its “low” graphics setting.

Well, the PhysX card is certainly consistent. Whether it’s sitting idle at the desktop or cranking away in CellFactor, it looks to add about 20 watts to the system’s total power draw. That’s not much in the grand scheme, and I can’t help but wonder whether the PhysX card wouldn’t draw more power if more fully utilized by software. The PhysX card does have an active cooling fan with variable fan speeds, and when it kicks into high gear, the fan definitely adds to overall system noise.

 
Conclusions
Clearly, Ageia faces some major hurdles in its quest to make physics processors a new must-have component of a PC gaming rig, but they’re making the logical and necessary steps to lay a foundation for success.

As for whether or not they’ll succeed, I have no idea.

Right now, it seems to me they have two very big problems. One, few games take advantage of the PhysX hardware at all, and the few that do don’t use the PPU’s processing power in a compelling way. Two, the most common physics elements in today’s games, rigid-body objects and particle effects, can be handled fairly well by high-end, dual-core CPUs, based on our CellFactor tests. That fact may narrow the PhysX cards’ primary selling points to the acceleration of things like fluids, cloth, and complex interactive particles. Ageia argues that offloading all physics to the PPU is good because it frees up CPU time, but it ain’t easy to sell folks on offloading a CPU core that would otherwise be largely idle.

Ageia may have a third big problem if it turns out that this first-gen PhysX PPU is simply a dog of a performer. We don’t have enough evidence draw that conclusion yet, but nothing I’ve seen so far convinces me this chip offers the sort of major leap in physics performance that Ageia claims for it. I remain hopeful, though, and we’ll be watching new PhysX-enabled games as they become available to see whether any of them deliver on PhysX’s promise. 

Comments closed
    • cRock
    • 13 years ago

    I think Ageia rushed this product out to door too soon. In a way, I don’t blame them. In a startup, you’re always under pressure to get a product into the market. You want to show everyone that you’re for real and having some money coming through the door makes the venture capitalist worry less.

    That said, they should have definately taken more time to bring a PCIe version of the hardware to market. I’m sure PCI was a lot easier and cheaper to implement, but it wasn’t worth it given the target market. They also needed have a big name title on board for the launch. They have that in Unreal, but lacked the patience to launch a refined product bundle. They may yet succeed, but they’re off to a rough start.

    In the long run, I think you’ll definately see a successful Direct X physics API with some type of hardware acceleration made possible. The best implemention may be run atop more mature general purpose FP coprocessors such as AMD is talking up in the server space. I’m sure you’ll also see this type of functionality creep into high-end GPUs. Ageia’s best hope is probably to sell out to NV or ATI before they’re left behind.

    • slot_one
    • 13 years ago

    Good review, bad product. I’m gonna get me a dual core AMD. Screw Agaya.

    • fyo
    • 13 years ago

    y[

    • fyo
    • 13 years ago

    Recursive car analogy error page 3 line 22:

    /[

    • Skyline57GTR
    • 13 years ago

    ATI claim their cards is best than Ageia PhysX for enough performance.

    • Hattig
    • 13 years ago

    Certainly I’d rather spend that money on a better graphics card and CPU right now.

    It’s first generation, so here’s hoping that it can be optimised and actually show a useful response in the future. They’ve done well in actually getting their API out, and actual hardware. However it really will require interactive physics (totally realistic, rather than approximations that most people are happy with anyway).

    I can see some games benefitting – realistic simulators for example. They could model airflow over surfaces, air pressure, humidity, etc (Flight Simulator seems an ideal target) which these people would pay money to have.

    When physics is used for eye candy effects, you’re (1) increasing the amount of stuff the graphics card needs to render, and (2) doing calculations on a card on a slow bus that are intended to be rendered on the other device. Complex physics (e.g., the cloths, fluids, etc) are good in this situation, but lots of small bodies … not so hot.

    Maybe if they modelled the vehicles and had accurate crash physics there’d be another compelling reason for the technology. Maybe they could model the blood flowing from your crushed legs after the engine has been thrust backwards into you after you crashed into a rock and didn’t amusingly bounce off it unharmed.

    • Freon
    • 13 years ago

    Good review. Pretty much what I expected.

    I won’t say Ageia is going to outright fail, but boy do they have a lot of big challenges.

    3D add-in graphics cards took hold so well because there was absolutely nothing comparable. No CPU could take on the same tasks and do so well.

    It seems Ageia isn’t getting that benefit with ATI and Nvidia looking to integrate comparable features in existing hardware, and likely succeeding in competing.

    Ageia is dreaming if they think they can create their own API, lock out competition, and keep developers blowing time on writing for an API for which only one company makes hardware. Look how fast direct support of 3Dfx cards died off in favor of OpenGL.

      • axeman
      • 13 years ago

      Plus physics don’t really have the “wow” factor of the first 3d graphics accelerators. I’m pretty sure most geeks remember the first time they saw a 3dfx card in action. Even the original Soundblaster was a bigger innovation than this thing. Physics co-processors are going to be a tough sell, especially when almost every new gaming rig is sitting their with a whole extra CPU core idling most of the time…

        • Bensam123
        • 13 years ago

        I don’t know about you but being able to pound a building in a tank till it finally crumbles to the ground in BF2 would certainly ‘wow’ me especially when it would crush all below it.

        Destroyable enviroments and realistic vehicle interactions with the enviroment would throw it over the top for me. Bullets that actually interact with the person that they hit?

          • axeman
          • 13 years ago

          AFAIK, this doesn’t really do this. All it does is fancy particle effects, plus loose a few FPS.

            • Bensam123
            • 13 years ago

            Did you guys even read to the part in the article where it says it does more then fancy debris effects?

          • Freon
          • 13 years ago

          They can’t make the buildings not crumble on computers without physics cards because you can’t expect 100% penetration. So you’re not buying the ability to ram a tank into a building. You’re just buying some more debris to be shown. Which probably just blocks your view and you’ll disable. 🙂

            • Kharnellius
            • 13 years ago

            Hmm. Have any of you seen the demo movie from the game Cell Factor? It seems you can do some pretty neat stuff with the card.

            §[<http://www.ageia.com/physx_in_action/cellfactor.html<]§ I suspect the biggest problem they have is the fact that not many games have truly shown its potential. The current games that use barely do and really make the product look worse rather than better.

          • BobbinThreadbare
          • 13 years ago

          All the rigid body physics can be done on your cpu per the article, so you don’t need the card to get that effect.

          • Bauxite
          • 13 years ago

          When they make something that lets me drive a tank in BF2 (or whatevers that kind of game at the time) through any 3rd world/florida construction type building on the map to get rid of an annoying sniper or whatnot, call me.

          If I can’t replicate a tiger or sherman through the european farmhouse often shown on the history channel (in multiplayer – scripting don’t count ya hear?) its not physics.

          Until then, all you companies can go away.

          Also, HL2 has pretty spiffy *usable ingame* physics and its from 2004…hmmmmmmm

            • Bensam123
            • 13 years ago

            I don’t know about that. You know what the easiest way to kill someone in CS:S is? You tip the cabinets over infront of them and it creates the best damn trap because the physics are so horrible. It’s like jumping onto a side of a pyramid. You think you’re on it but you just slide back off.

            I’ve seen countless people get gunned down because they can’t get over tipped over physic objects in game.

            Same thing goes for the desk chairs in office and countless other objects. They’re very poor representations as far as what can be done with something like this.

            • Bauxite
            • 13 years ago

            Thats in multiplayer, source physics is dumbed down quite a bit there. I’d play HL2 DM/CTF more often if it wasn’t.

            Fire up HL2 SP again and try it out in one of their ‘we only made this to show off our physics’ areas. Now add 2 years and say “wtf is going on game developers?”.

        • Freon
        • 13 years ago

        Yeah, when GLQuake came out it was on.

        Going from software render at 20FPS to 40fps, with bilinear mipmapping and colored lights, for like $150. It was awesome.

        But it still took a few years after the Voodoo 1 was released for the market to settle. Even with such a clear cost to benefit. It made gaming what it is today.

        This is like an extra bump on the debris slider. It isn’t a 100% performance improvement, huge full screen image quality bump. It’s more like just getting just the colored lights for twice the price and a performance loss. No thanks, I’ll wait a year or two for some early adopters to soak up some cost.

          • fyo
          • 13 years ago

          Depending on your hardware (CPU), framerates actually DECREASED. Add to that the small, but very noticable, LAG that the VooDoo cards introduced, and “all” 3dfx offered was a bit of shiny graphics. glQuake was very well done, however, and Ageia should have done the exact same thing (see my post elsewhere in these comments for more info).

          I was into the whole competitive gaming scene at the time and it wasn’t until the VooDoo 2 that 3D cards really converted the serious gamers (with a few notable exceptions, mostly paid for by 3dfx or other hardware vendors). And even then, software rendering still had a sizeable following for as long as the game support remained. The frame rates had gone up, but the 3D card lag was still there… and still is to this day. People have just gotten used to it and since there is no alternative, no one even mentions it anymore (probably no one even notices anymore, since the “snappy” alternative with software rendering isn’t available to show the contrast).

            • BobbinThreadbare
            • 13 years ago

            I don’t experience any lag at all. I play Doom 1 from time to time (which is being rendered in software), and it doesn’t seem any snappier than my accelerated games.

            • Bauxite
            • 13 years ago

            You’re on crack.

            I had the fastest available CPU when GL quake was released, I went from some crap rez like 320×240 to 640×480 and my fps went way up.

            As for lag there was none and we could only play on a LAN at the time, a place you would notice anything more than a few ms, since our ‘uber’ LAN was one 24 port switch (most people were still in hubland then) and cables. Even if you still use a highend CRT your delay is up to 5ms @ 200hz, everyone is probably 60~75hz on a LCD now though. (they invented something called vertical sync, yay)

            This is from someone who can feel the difference between stocked clocked PS/2 mice before and after the increased refresh rate. (I eventually shorted out several different mice and one motherboard connector at 200hz until I found one that would stick…gotta love how those things use soldered in fuses if any) I’d still like to find something to make USB mice a little better, but at least the ball is dead for good.

            • Buub
            • 13 years ago

            Agreed. I had a Pentium 120 at the time and framerates were passable in Descent 2. Once I plugged in that Voodoo card, man, framerates went through the roof *and* the texture quality was improved. The Voodoo increased framerates substantially.

    • Chrispy_
    • 13 years ago

    PhysX makes a noticeable difference to single core, slow-clocked machines but a negligible difference to dual core machines.

    For a $300 card though, it just seems that the money is far, far better spent on getting more cores than thumping it down onto a card which is, as of yet, unproven and with a somewhat shaky future.

    • Bensam123
    • 13 years ago

    Two benchmarks FTW!

    If the PPU is all Ageia works it up to be you would wonder why they don’t tread on others territory and lay the smack down (by accelerating Havok and DX10). Of course it would be bad for their own API but sometimes you gotta throw your weight around if you want to show people where it’s really at plus giving their card extremely large amounts of compatability others will sell the card for you.

    Maybe the issue is a bit more complicated then accelerating someone elses API, hopefully they won’t go the way of the BetaMAX.

    • kilkennycat
    • 13 years ago

    Dead duck for many of the reasons listed in the article and reader comments. However, the biggest immediate killer is the lack of a PCIe version. The guys that are likely to be the essential ‘early adopters’ of this turkey… I mean duck…. are those that already have dual-SLI or Crossfire PCIe gaming rigs… the guys to whom a few more $$$ means nothing in their pursuit of PC gaming perfection. However, you will note that on a PCIe motherboard with dual high-end SLI/Crossfire cards there is only 1 motherboard PCI slot still free ( that is not either covered by two double-width video cards or needs to be left free for adequate cooling of 2 single-slot video cards). And that final PCI slot is already occupied by a high-end audio-card ( X-Fi or similar). Meanwhile, there is usually a PCIe X1 or X4 slot still free. Ageia seems to have a bunch of amateurs in their organization with regard to the execution of their hardware strategy. Ageia might have been a lot better off licensing their hardware IP to nVidia or Ati. Ageia is very coy about what is in the chip — so maybe the Emperor has no clothes and their hardware technology is just not worth licensing anyway, and a modern general-purpose DSP as a co-processor on the motherboard could handle it all better at a fraction of the PPU cost. After all, DSPs have been used for many years for high-powered math computations, including complex physics. AMD is currently exploring the notion of motherboard co-processors in ‘spare’ AM2 sockets working seamlessly with their CPUs. Anyway, the Havok FX dual-prong attack on the physics issues, seamlessly combining the capabilities of multicore CPUs (for gameplay physics) with SM3.0 (or higher)- capable GPUs ( for effects physics) has been embraced by the power-house graphics guys, especially nVidia.

    For more on Havok FX, see:-

    §[<http://www.havok.com/content/view/187/77/<]§

    • shank15217
    • 13 years ago

    I said this before in another post, its not the PCI bus, I dont think physics processing is bandwidth limited, it is however Latency limited. I think a lot of performance is lost just getting the data to the PPU and the results back. This is obvious from damage’s dual core results. The second cpu is much closer to memory and can significantly increase performance just with latency alone. PPUs belong right next to the CPU not on an aged defunked bus.. Its like putting a 7900GTX on the pci bus.

    • GhostDawg
    • 13 years ago

    Nice reveiw……………but its just another complexity that will cause bugs in PC games and push Joe Six pack to the new gen of consoles.

    • lethal
    • 13 years ago

    look promising but not ready for prime time. BTW I think the first comparison in page 6 is backwards.

    • Trident Troll
    • 13 years ago

    Ok, time for my own “64k is enough for anybody” moment.

    Discrete physics processors are a dead end.
    Unless a game’s main ‘feature’ is an interactive world with realistic physical behaviors for all objects, game studios just won’t be able to put in the time necessary to fully develop elaborate physics systems (and designing the gameplay to make it worthwhile) for their games. Eventually, an accepted minimum level of world physics will be settled upon by both sides (developers and consumers) that will be perfectly happy running on the resident CPU of a gamer’s system.
    That’s my prediction.

      • willyolio
      • 13 years ago

      y[

      • spiritwalker2222
      • 13 years ago

      You’ve miss quoted it’s 640K

        • Trident Troll
        • 13 years ago

        Nope, that’s a typo. And I’m too lazy to correct it. But not too lazy, apparently, to respond to you. Weird, huh?

    • FroBozz_Inc
    • 13 years ago

    The whole concept of having to pay for another card, taking up another slot in my computer…Well it’s nuts to me.
    The SLI concept is bad enough. Now you have future three card senarios. Bah.

    The only way I think this concept is going to fly is if nVidia and ATI integrate the technology on all their mid/highend cards standard across the board. The idea of being able to have a 2nd or third graphics card re-dedicated as the physics processor is an improvement, giving you some flexibility. But, I still think the only real way you’ll see mass-adoption is if it comes integrated on graphics cards.

    • Ruiner
    • 13 years ago

    Ageia would have made a much smarter move selling their API to one of the GPU or CPU companies.
    Hybrid/dual core gpu/ppu on one card anyone?

    How about cpu/cpu/gpu/ppu on a single quad core?

      • shank15217
      • 13 years ago

      Integrated solutions dont work in the enthusiast pc industry. One part of the product is always obsolete before the others and is rendered useless or worse, degrades performance of other parts.

        • Chrispy_
        • 13 years ago

        Everyone was happier when GPU’s were added to 2d display adapters. I sure hated having completely seperate 3D cards and 2D accellerators – it was just more drivers and compatibility to worry about.

        What’s the difference with physics and graphics being merged?

          • axeman
          • 13 years ago

          Because 2d and 3d are both graphics? Why doesn’t you whine about the lack of graphics adapters with integrated sound, too, while you’re at it?

            • Ruiner
            • 13 years ago

            You don’t have to. The sound is on the mobo, and it’s ‘good enough’ for the majority. I could see GPU and PPU tech maturing at the same pace. It would be a decent match for a single core (or at least single card).

    • wmgriffith
    • 13 years ago

    From the article: “Physics is not graphics.” Why is the only discussion about framerate?

    The PPU is supposed to make your game more realistic, so we should accept that framerate won’t tell the story. OTOH, Ageia has not given you the tools by which you can make the comparison you want to make, which is PPU vs. no-PPU.

    So, where are the BLAS and LAPACK benchmarks? Gravitational simulations? Can someone independent of Ageia consult Tipler and run an apples-to-apples comparison of the same calculations? You don’t need pretty graphics for that.

      • BobbinThreadbare
      • 13 years ago

      It should give you physics without slowing down your machine. If the $300 add in card slows down your expenisive graphics system, it’s not worth it.

      Also, unless they think people are going to buy a new one every year, it needs to last a while, which means it should be fast enough that you don’t need to upgrade it for 2-3 years.

        • SGWB
        • 13 years ago

        The way games publishers are using the PhysX chip, even if it had an ideal implementation it would degrade graphics performance. They are putting more objects on screen for the GPU to cope with, so you will get fewer frames per second. Admittedly, the PhysX add in boards we have seen are far from an ideal implementation. But, it would be nice to see a game use physics accelleration used for real gameplay insetad of graphic effects.

        No matter whether it uses the PhysX, GPU based accelleration, or leverages the CPU, I don’t expect to see game affecting physics untill Microsoft releases their physics API. No game company will want to tie their product to a particular piece of hardware with a proprietary API again. Well, unless MS is backing it.

          • BobbinThreadbare
          • 13 years ago

          The graphics card TR uses can run a demanding game like FEAR at 57.5 FPS, but can’t get through Cell Factor at more than 37.5? I’m not buying it (pun intended).

    • Spotpuff
    • 13 years ago

    There is no way I am spending more on this than my graphics card. For such a minor contribution this thing is way overpriced.

      • Vhalidictes
      • 13 years ago

      It’s not that it’s overpriced, or does a poor job. Those wouldn’t be deal-breakers.

      It’s that CPU manufacurers are desperate to provide more value in games, and dual-core CPUs largely invalidate the current PhysX concept.

      Their own (excellent and needed-for-adoption) API is killing them.

      It’s really a lose-lose, which is a shame, since I really like the idea of physics giving gameplay opportinities.

        • Kharnellius
        • 13 years ago

        Very well said and I agree. :tup:

    • spiritwalker2222
    • 13 years ago

    When will we see an actual comparison???
    I’d like to see this thing run against a CPU doing the computations or a video card.

      • droopy1592
      • 13 years ago

      ? Wasn’t there one in the review?

      • moose103
      • 13 years ago

      Great review, as always.

      All the PhysX card is doing is calculating their LOCATION/INTERACTION.

      But no one seems to realize all extra particles need to be drawn on the screen by the graphics card. Of course it will slow down!

    • Logan[TeamX]
    • 13 years ago

    Great review. I, too, think that the dang thing belongs on a good-sized pipe of PCI-E connectivity.

    PCI… 133MB/sec. PCI-E x4… over 1GB/sec if memory serves. I have a feeling the difference would be rather profound provided the game was exploiting the PPU as advertised.

    • spuppy
    • 13 years ago

    Holy crap I didn’t realize this thing adds 10-20% to power consumption!

    • Shintai
    • 13 years ago

    Maybe this will change in….2008 😉

    Currently I see no reason to get a 250-300$ PPU. I would maybe think about it, if it was around 50$ and without a fan, PCIe interface and there was some more improvement.

    But I cast my vote on more CPU cores and GPUs to do it.

    • droopy1592
    • 13 years ago

    BIG FAT MEH

    Good review though

    • Jigar
    • 13 years ago

    Good job scott… I better wait for K8L … and when its launch, i will rather use 2 cores for Phsy.. and call it a day… 🙂

    • blastdoor
    • 13 years ago

    I think this provides some pretty compelling evidence that all of us who have been saying we’d rather just use the second core in our dual core CPU to do physics than get a PPU are going to be very happy with our ability to enjoy physics effects in games.

    • Archer
    • 13 years ago

    Abs…laff. ROTTD was a fun game, I’ve forgotten all about it.

    PhysX? $300? No thanks.

      • Usacomp2k3
      • 13 years ago

      Impossible. No one can forget it 8)

    • indeego
    • 13 years ago

    “Physics is not graphics. ”
    In this imple\mentation it is. 100% of the physics we are seeing in your demos is relating to particles that don’t effect total gameplay.

    “Eye candy isn’t interactivity.”
    Nope, but neither is physics interactivity.

    I think that is all you need to come away with, with this product. This card doesn’t change the game, only the “look” of the game. After you’ve seen the look enough times, it gets old, and you want to fall back on the game itself.

    Don’t buy a product that makes you *[

      • absinthexl
      • 13 years ago

      y[

    • FubbHead
    • 13 years ago

    This seems more like console hardware to me at the moment.

    • DrDillyBar
    • 13 years ago

    I want my Folding@Home!!! (to the tune of Money for Nothing)
    Word up to #5.

    • lyc
    • 13 years ago

    another excellent, comprehensive review; well done 🙂

    • Forge
    • 13 years ago

    Maybe the PCIe version will *accelerate* things instead of just adding more things and making things slower.

    Course, if Ageia can’t get something wow going soon, they’ll never have the install base to do anything later.

      • Wajo
      • 13 years ago

      They should pay a game studio to make an absolutely kicka$$ game that required the PPU and bundle it with their cards.

        • nerdrage
        • 13 years ago

        Good idea… that’s the only way I can see this thing getting any market share. This product definitely doesn’t have the 3dfx/GLQuake “wow” factor (the last successful piece of addon hardware). Without a “killer app”, this is going nowhere.

        PPUs seem to me like an expensive solution looking for a problem. Using a second CPU or GPU core to do the same thing seems like a much more sensible thing to do.

          • 5150
          • 13 years ago

          *cough*Duke*cough*Nukem*cough*

            • nerdrage
            • 13 years ago

            Nah, that’ll just give them yet *another* excuse to delay the game. But can you imagine the Duke Nukem physics possibilities? Prostitutes with realistic chest “movements”… lol

    • absinthexl
    • 13 years ago

    I love the GRAW screenshots. I’m getting flashbacks of Rise of the Triad’s “Ludicrous Gibs.”

    I wonder how useful cloth and fluid effects really are – and more importantly, I can’t imagine them being worth $300 at this point. What are the practical applications, beyond tapestries, waterfalls and water with heavy waves? After all, the addition of physics to games is pretty big, especially after remembering how objects were thrown around in System Shock 2 and the original Deus Ex (beakers would stay perfectly upright throughout their flight). Character cloth is put directly into the animation right now (automatically, by the way), and their flamethrower demonstration doesn’t even look as good as the one in the five-year-old Return to Castle Wolfenstein.

    • coldpower27
    • 13 years ago

    Well it’s a start for the PPU but 4 FPS isn’t exactly what I would call the make or break you deal.

    Though the PPU does make sense if it can do certain effects that the CPU can’t do at all.

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