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This is version 2 of the FAQ located here. I have attempted to compile, clean up, and update all the information in that thread, as well as some additional information. If you have any comments, please put them in the original FAQ thread, and I will make the changes here. Mods, feel free to do whatever you want to this thread and the info here.
Thanks for your help!
Q: What is a PPU?
A: It is a dedicated processor designed to handle the calculations of physics, especially in video games. Examples of calculations a PPU might do include rigid body dynamics, soft body dynamics, collision detection, fluid dynamics, hair and clothing simulation, finite element analysis, and fracturing of objects. The idea is that specialized processors can do quickly what would take longer for a CPU, analogous to the way a GPU performs optimized graphics operations. Currently, the PhysX is only offered in regular PCI versions, not PCI-express.
Q: What is Novadex?
A: Novadex is the former name of Ageias physics engine, now known as PhysX API. A game developer must license the PhysX physics engine for use in their games. Ageia gives PhysX licenses for free if the game developer will program their game to take advantage of the PhysX accelerator. Ageia has also developed tools for working with PhysX on the PS3 and Xbox 360. The multi-core CPUs of the PS3 in particular should work well with the highly-threaded nature of the PhysX engine.
Only games using version 2.3 of the PhysX engine or newer will work with the PPU. 2.4 is the current version. Games such as Bet on Solder, which uses version 2.2, will receive a patch soon, others may follow.
The Havok physics engine, in contrast, costs hundreds of thousands of dollars to license for development in a game.
Q: What is the difference between effects physics processing and gameplay physics processing?
http://enthusiast.hardocp.com/article.html?art=MTA5NywxLCxoZW50aHVzaWFzdA==http://enthusiast.hardocp.com/article.html?art=MTA5NywxLCxoZW50aHVzaWFzdA==http://enthusiast.hardocp.com/article.html?art=MTA5NywxLCxoZW50aHVzaWFzdA==This HardOCP interview between ATI, NVIDIA, Havok and Ageia will give you all the answers you need on this topic.
A: Effects physics processing is only a visual effect, and doesnt affect gameplay in a substantial way. Examples of effects physics enhancements would be larger explosions, debris, shrapnel, and death animations. Gameplay physics would be the ability to use objects in a game world to impact other things in the game world. Like characters being killed by shrapnel from an explosion, or from flying objects as a result of an explosion. Here are some demo videos from NVIDIA and ATI: http://hardforum.com/showthread.php?t=1034977
Q: Exactly what enhancements will I see in future games if I have one of these cards?
A: There are several advantages. The first is more active bodies - movable, deformable objects in the game. Whereas a CPU can only do about 500 of these, a dedicated PPU can do thousands. More active bodies means more shrapnel in explosions and destructible environments that realistically create debris and impact the game world. The second stage of development is advanced physics calculations such as velocity, force, and stopping power. For example, with a PPU in your system and a game that supports it, a bullet could be shot through a wall. Depending on the material and thickness of the wall, mass and speed of the bullet, and distance to the player behind the wall whom the bullet will hit, the PPU will decide whether the bullet will have enough force left to either A. Inflict a superficial wound and stun the player for a few seconds, B. Cause damage to the player, or C. Kill the player.
Q: Are there other methods to process physics? What about the Havok physics engine?
A: NVIDIA has partnered with the makers of the Havok engine to allow for physics processing to be done on a Shader Model 3.0 compatible GPU. They have developed Havoc FX, which is an addition to Havok's standard physics engine. A game must use the standard Havok engine, and have the Havok FX code add-on to benefit from acceleration on a SM3.0 GPU. However, the performance impact of processing both video and physics on a GPU at the same time is yet-to-be-determined. At this point, it appears the Havok implementation only supports effects physics. The advantage here is accelerated physics can be handled by already existing hardware, without the investment into a standalone PPU. Though nVidia has partnered with Havok to further this technology, both Havok and Ati have claimed that Atis SM3.0 GPUs are able to accelerate Havok FX as well.
Q: Could I utilize the second GPU in an SLI/Crossfire setup to do physics processing?
A: Yes, but keep in mind that if you dedicate 1 GPU in an SLI setup to physics, you will only have 1 GPU doing the actual graphics. If you already have SLI, it would be a good idea to dedicate one of them to physics if you wanted to play physics-enabled games but didn't want to buy a PPU. If you don't have SLI, however, it may be cheaper to buy a PPU than to buy a second GPU for physics. It is unclear at this point exactly how Atis Crossfire solution will handle physics rendering.
Q: Can I use an older GPU to accelerate physics alongside a new GPU doing graphics?
A: We won't be sure until NVIDIA or ATI officially release drivers that support GPU physics processing. ATI has said that it will allow R520 cards to do physics alongside R580 cards. It seems NVIDIA, however, will require identical cards in SLI.
Q: What games use the PhysX PPU?
A: At this point, only a few. Ghost Recon: Advanced Warfighter is credited with being the first major game to support hardware accelerated physics. However, the effects are minimal: the only impact a PPU appears to have is an increase in the amount of shrapnel and debris from explosions. These effects are not terribly impressive, resulting in large chunks of generic looking debris flying through the world, but no impact on the gameplay. Bet on Soldier adds a fluid flamethrower weapon to PPU equipped PCs, but the effect is far from earth-shattering.
Easily the most impressive game available is the Cell Factor demo. This game involves a deathmatch set in a wide open area with boxes and barrels stacked several stories tall. The player has the ability to push and pull these objects, or place a grenade in the middle of these piles. The effects evident in this demo truly demonstrate what physics accelerators are capable of.
There is an impressive list of upcoming games on Ageias website, most notably Unreal Tournament 2007.
Here are some demo videos of the PPU: http://hardforum.com/showthread.php?t=1034714
Q: Where can I buy the PhysX?
A: They are available online at retailers such as Newegg, and should be available at B&M retailers such as Best Buy as well. The MSRP is $299.
Q: Can't you just use a dual-core CPU to do physics?
A: Not according to Ageia or Havok. They report that a dual-core CPU can handle about 1,000 objects. CPUs are designed with general purpose computing in mind. This is a good thing, because CPUs are very versatile. However, like a GPU, a PPU is designed specifically to process physics calculations, and this specific engineering allows a PPU to handle up to 20,000 objects, according to Ageia. A GPU, by nature, is more prepared to handle physics calculations than a CPU, and therefore can handle thousands of objects, according to Havok.
Q: If I buy a game designed for use with a PPU, can I use a GPU or a CPU to do the physics processing?
A: This will depend on the game developers. Ghost Recon: Advanced Warfighter will run physics effects in software mode on non-PPU enabled systems. This means that the CPU is handling physics. Cell Factor, on the other hand, will require a PhysX PPU to run. The PhysX and Havok FX engines are capable of running in software mode on CPUs, and it is up to game developers to decide how to implement this feature.
Q: Will a GPU physics solution be able to do both gameplay and effects physics?
A: Not at this time. This is a common misconception. Havok has stated that a GPU can only do effects physics, meaning that it will not affect the environment with things like flying shrapnel. You will see the shrapnel, but it won't be able to hit players, go through walls, deform the terrain...etc.
Q: Will a PPU affect non-optimized games?
A: No. Games have to be specially programmed to take advantage of the PPU using Ageias PhysX engine. Some developers, however, may choose to release a patch for their current games which would allow them to take advantage of the PPU.
Q: Can the PhysX be overclocked?
A: We don't know for sure yet. The chip it appears to be clocked in the ranges 250-266MHz or 500-533MHz, based on some early in-house codes (Ageia has been secretive about its details), and there is always a way to make a chip run faster. However, it is unclear if there is a software method to control the PPUs clock speed, or if changing the clock speed would require extensive hardware modifications. For the foreseeable future, there isnt any reason to overclock it, though, because games won't be reaching the hardwares maximum potential. Some detailed specs can be found here.
Q: Will there be other PPU models?
A: It's anyone's guess. It could become like the video card market, with good/better/best models available, and games would have "physics options" that could be turned up or down to allow someone with an older PPU to play the game. Or, it could end up like the sound card market with EAX, where your card merely has to support the engine, without concern for performance.
Q: What if other physics standards come out? Can the PhysX work with them?
A: Microsoft is creating a common physics API, which will likely be integrated as part of a future version of DirectX. Ageia has said their PPU is highly programmable, and can therefore be used to accelerate Havok, future versions of PhysX, or conceivably any other physics engine. Therefore, in theory, new drivers from Ageia would enable support for Microsofts DirectX physics.
Q: I see that 3dmark06 has the AGEIA logo on it; will a PPU increase my score?
A: At the moment it will make no difference. This could be because it uses a version of the engine older than 2.3 (files in the directory have version numbers removed) or perhaps it is set to only use the CPU in software mode.
Q: I have an older system, will a PPU make it run faster?
A: Not likely. If your video card is having a hard time rendering a game now, then it will only get worse when it tries to render the 1,000s of objects a PPU can support. However, if you have a fast video card already, and games performance is being held back by your systems CPU, then a PPU will reduce the load on your CPU, and will increase your performance. Again, this only applies to PhysX enabled games.
Q: Is there a PCI-express version coming out?
A: Not at this point. Early versions of the card showed both PCI and PCI-e connectors on the same card, but it was revealed that these early models were merely tech demos, and the dual connector was not possible on retail cards.
Q: Why does the PhysX use the lowly PCI bus?
A: This initially seems odd as the PCI bus can only move data at 132MB/s while PCIe x16 can do 4,000MB/s (theoretical numbers). The PPU doesn't have to deal with textures, which is a huge part of a video cards bandwidth use. Also, the PPU would only need to send out data for the objects that are moving or interacting at any one point in time (so of the 5000 objects that the PPU is tracking, only 100 of them might need their positions to be updated at any one time). You can read Tim Sweeneys (creator of Unreal Engine) thoughts on this subject here:
http://www.gamespot.com/news/2005/0...ws_6119896.html
Q: Will having a PhysX card in my PC cause Havok games not to work?
A: No. The PhysX will simply be idle any time it isnt accelerating a PhysX game.
Q: I heard the PPU actually decreases framerates, is this true?
A: Initially, yes, and to some extent, it still does. In GRAW, initial benchmarks showed the PPU-enabled version of the game ran at a significantly lower framerate than without the PPU running. Ageia heard the outcry of the community, and released a new driver quickly.
Q: How will online multiplayer games handle the PPU?
A: There is much conjecture surrounding this subject. Effects physics should be no problem in online multiplayer games, since the effects will be merely visual, and will only be seen by those players with a PPU in their PC. Gameplay physics present a significant problem though. Either every player must have a PPU, and the game server will simply broadcast position data as it does now, with physics calculations handled by each players PPU. OR, it also may be possible for the game server to have a PPU, and then a PPU would not be a requirement for each system. The problem with this solution is an extreme amount of bandwidth required to maintain positions of every object, individual pieces of shrapnel, even puffs of smoke. It is unknown how game developers will attempt to attack this issue. At this point, the Cell Factor demo can only be played on a LAN. Tim Sweeney, creator of the Unreal Engine and UT2007, shared his thoughts in an interview.
Q: Are 64-bit drivers available?
A: Not as of 5/11/06. Updated drivers can be downloaded at Ageias website as they are released. Ageia has said they are working on this.
Q: Can you watercool a PPU?
A: Is this HardOCP or not??
Thanks for your help!
Q: What is a PPU?
A: It is a dedicated processor designed to handle the calculations of physics, especially in video games. Examples of calculations a PPU might do include rigid body dynamics, soft body dynamics, collision detection, fluid dynamics, hair and clothing simulation, finite element analysis, and fracturing of objects. The idea is that specialized processors can do quickly what would take longer for a CPU, analogous to the way a GPU performs optimized graphics operations. Currently, the PhysX is only offered in regular PCI versions, not PCI-express.
Q: What is Novadex?
A: Novadex is the former name of Ageias physics engine, now known as PhysX API. A game developer must license the PhysX physics engine for use in their games. Ageia gives PhysX licenses for free if the game developer will program their game to take advantage of the PhysX accelerator. Ageia has also developed tools for working with PhysX on the PS3 and Xbox 360. The multi-core CPUs of the PS3 in particular should work well with the highly-threaded nature of the PhysX engine.
Only games using version 2.3 of the PhysX engine or newer will work with the PPU. 2.4 is the current version. Games such as Bet on Solder, which uses version 2.2, will receive a patch soon, others may follow.
The Havok physics engine, in contrast, costs hundreds of thousands of dollars to license for development in a game.
Q: What is the difference between effects physics processing and gameplay physics processing?
http://enthusiast.hardocp.com/article.html?art=MTA5NywxLCxoZW50aHVzaWFzdA==http://enthusiast.hardocp.com/article.html?art=MTA5NywxLCxoZW50aHVzaWFzdA==http://enthusiast.hardocp.com/article.html?art=MTA5NywxLCxoZW50aHVzaWFzdA==This HardOCP interview between ATI, NVIDIA, Havok and Ageia will give you all the answers you need on this topic.
A: Effects physics processing is only a visual effect, and doesnt affect gameplay in a substantial way. Examples of effects physics enhancements would be larger explosions, debris, shrapnel, and death animations. Gameplay physics would be the ability to use objects in a game world to impact other things in the game world. Like characters being killed by shrapnel from an explosion, or from flying objects as a result of an explosion. Here are some demo videos from NVIDIA and ATI: http://hardforum.com/showthread.php?t=1034977
Q: Exactly what enhancements will I see in future games if I have one of these cards?
A: There are several advantages. The first is more active bodies - movable, deformable objects in the game. Whereas a CPU can only do about 500 of these, a dedicated PPU can do thousands. More active bodies means more shrapnel in explosions and destructible environments that realistically create debris and impact the game world. The second stage of development is advanced physics calculations such as velocity, force, and stopping power. For example, with a PPU in your system and a game that supports it, a bullet could be shot through a wall. Depending on the material and thickness of the wall, mass and speed of the bullet, and distance to the player behind the wall whom the bullet will hit, the PPU will decide whether the bullet will have enough force left to either A. Inflict a superficial wound and stun the player for a few seconds, B. Cause damage to the player, or C. Kill the player.
Q: Are there other methods to process physics? What about the Havok physics engine?
A: NVIDIA has partnered with the makers of the Havok engine to allow for physics processing to be done on a Shader Model 3.0 compatible GPU. They have developed Havoc FX, which is an addition to Havok's standard physics engine. A game must use the standard Havok engine, and have the Havok FX code add-on to benefit from acceleration on a SM3.0 GPU. However, the performance impact of processing both video and physics on a GPU at the same time is yet-to-be-determined. At this point, it appears the Havok implementation only supports effects physics. The advantage here is accelerated physics can be handled by already existing hardware, without the investment into a standalone PPU. Though nVidia has partnered with Havok to further this technology, both Havok and Ati have claimed that Atis SM3.0 GPUs are able to accelerate Havok FX as well.
Q: Could I utilize the second GPU in an SLI/Crossfire setup to do physics processing?
A: Yes, but keep in mind that if you dedicate 1 GPU in an SLI setup to physics, you will only have 1 GPU doing the actual graphics. If you already have SLI, it would be a good idea to dedicate one of them to physics if you wanted to play physics-enabled games but didn't want to buy a PPU. If you don't have SLI, however, it may be cheaper to buy a PPU than to buy a second GPU for physics. It is unclear at this point exactly how Atis Crossfire solution will handle physics rendering.
Q: Can I use an older GPU to accelerate physics alongside a new GPU doing graphics?
A: We won't be sure until NVIDIA or ATI officially release drivers that support GPU physics processing. ATI has said that it will allow R520 cards to do physics alongside R580 cards. It seems NVIDIA, however, will require identical cards in SLI.
Q: What games use the PhysX PPU?
A: At this point, only a few. Ghost Recon: Advanced Warfighter is credited with being the first major game to support hardware accelerated physics. However, the effects are minimal: the only impact a PPU appears to have is an increase in the amount of shrapnel and debris from explosions. These effects are not terribly impressive, resulting in large chunks of generic looking debris flying through the world, but no impact on the gameplay. Bet on Soldier adds a fluid flamethrower weapon to PPU equipped PCs, but the effect is far from earth-shattering.
Easily the most impressive game available is the Cell Factor demo. This game involves a deathmatch set in a wide open area with boxes and barrels stacked several stories tall. The player has the ability to push and pull these objects, or place a grenade in the middle of these piles. The effects evident in this demo truly demonstrate what physics accelerators are capable of.
There is an impressive list of upcoming games on Ageias website, most notably Unreal Tournament 2007.
Here are some demo videos of the PPU: http://hardforum.com/showthread.php?t=1034714
Q: Where can I buy the PhysX?
A: They are available online at retailers such as Newegg, and should be available at B&M retailers such as Best Buy as well. The MSRP is $299.
Q: Can't you just use a dual-core CPU to do physics?
A: Not according to Ageia or Havok. They report that a dual-core CPU can handle about 1,000 objects. CPUs are designed with general purpose computing in mind. This is a good thing, because CPUs are very versatile. However, like a GPU, a PPU is designed specifically to process physics calculations, and this specific engineering allows a PPU to handle up to 20,000 objects, according to Ageia. A GPU, by nature, is more prepared to handle physics calculations than a CPU, and therefore can handle thousands of objects, according to Havok.
Q: If I buy a game designed for use with a PPU, can I use a GPU or a CPU to do the physics processing?
A: This will depend on the game developers. Ghost Recon: Advanced Warfighter will run physics effects in software mode on non-PPU enabled systems. This means that the CPU is handling physics. Cell Factor, on the other hand, will require a PhysX PPU to run. The PhysX and Havok FX engines are capable of running in software mode on CPUs, and it is up to game developers to decide how to implement this feature.
Q: Will a GPU physics solution be able to do both gameplay and effects physics?
A: Not at this time. This is a common misconception. Havok has stated that a GPU can only do effects physics, meaning that it will not affect the environment with things like flying shrapnel. You will see the shrapnel, but it won't be able to hit players, go through walls, deform the terrain...etc.
Q: Will a PPU affect non-optimized games?
A: No. Games have to be specially programmed to take advantage of the PPU using Ageias PhysX engine. Some developers, however, may choose to release a patch for their current games which would allow them to take advantage of the PPU.
Q: Can the PhysX be overclocked?
A: We don't know for sure yet. The chip it appears to be clocked in the ranges 250-266MHz or 500-533MHz, based on some early in-house codes (Ageia has been secretive about its details), and there is always a way to make a chip run faster. However, it is unclear if there is a software method to control the PPUs clock speed, or if changing the clock speed would require extensive hardware modifications. For the foreseeable future, there isnt any reason to overclock it, though, because games won't be reaching the hardwares maximum potential. Some detailed specs can be found here.
Q: Will there be other PPU models?
A: It's anyone's guess. It could become like the video card market, with good/better/best models available, and games would have "physics options" that could be turned up or down to allow someone with an older PPU to play the game. Or, it could end up like the sound card market with EAX, where your card merely has to support the engine, without concern for performance.
Q: What if other physics standards come out? Can the PhysX work with them?
A: Microsoft is creating a common physics API, which will likely be integrated as part of a future version of DirectX. Ageia has said their PPU is highly programmable, and can therefore be used to accelerate Havok, future versions of PhysX, or conceivably any other physics engine. Therefore, in theory, new drivers from Ageia would enable support for Microsofts DirectX physics.
Q: I see that 3dmark06 has the AGEIA logo on it; will a PPU increase my score?
A: At the moment it will make no difference. This could be because it uses a version of the engine older than 2.3 (files in the directory have version numbers removed) or perhaps it is set to only use the CPU in software mode.
Q: I have an older system, will a PPU make it run faster?
A: Not likely. If your video card is having a hard time rendering a game now, then it will only get worse when it tries to render the 1,000s of objects a PPU can support. However, if you have a fast video card already, and games performance is being held back by your systems CPU, then a PPU will reduce the load on your CPU, and will increase your performance. Again, this only applies to PhysX enabled games.
Q: Is there a PCI-express version coming out?
A: Not at this point. Early versions of the card showed both PCI and PCI-e connectors on the same card, but it was revealed that these early models were merely tech demos, and the dual connector was not possible on retail cards.
Q: Why does the PhysX use the lowly PCI bus?
A: This initially seems odd as the PCI bus can only move data at 132MB/s while PCIe x16 can do 4,000MB/s (theoretical numbers). The PPU doesn't have to deal with textures, which is a huge part of a video cards bandwidth use. Also, the PPU would only need to send out data for the objects that are moving or interacting at any one point in time (so of the 5000 objects that the PPU is tracking, only 100 of them might need their positions to be updated at any one time). You can read Tim Sweeneys (creator of Unreal Engine) thoughts on this subject here:
http://www.gamespot.com/news/2005/0...ws_6119896.html
Q: Will having a PhysX card in my PC cause Havok games not to work?
A: No. The PhysX will simply be idle any time it isnt accelerating a PhysX game.
Q: I heard the PPU actually decreases framerates, is this true?
A: Initially, yes, and to some extent, it still does. In GRAW, initial benchmarks showed the PPU-enabled version of the game ran at a significantly lower framerate than without the PPU running. Ageia heard the outcry of the community, and released a new driver quickly.
Some benchmarks Firingsquad ran with the new driver substantiated Ageias claim. However, further investigation revealed that in a high end Crossfire setup with two X1900XTXs, the PhysX mode still ran slightly slower, albeit at speeds that one would never notice (higher than 80 FPS).
Q: How will online multiplayer games handle the PPU?
A: There is much conjecture surrounding this subject. Effects physics should be no problem in online multiplayer games, since the effects will be merely visual, and will only be seen by those players with a PPU in their PC. Gameplay physics present a significant problem though. Either every player must have a PPU, and the game server will simply broadcast position data as it does now, with physics calculations handled by each players PPU. OR, it also may be possible for the game server to have a PPU, and then a PPU would not be a requirement for each system. The problem with this solution is an extreme amount of bandwidth required to maintain positions of every object, individual pieces of shrapnel, even puffs of smoke. It is unknown how game developers will attempt to attack this issue. At this point, the Cell Factor demo can only be played on a LAN. Tim Sweeney, creator of the Unreal Engine and UT2007, shared his thoughts in an interview.
Q: Are 64-bit drivers available?
A: Not as of 5/11/06. Updated drivers can be downloaded at Ageias website as they are released. Ageia has said they are working on this.
Q: Can you watercool a PPU?
A: Is this HardOCP or not??