PCs have an abundance of RAM/HD/VRAM space, using lack of memory as an excuse why PhysX debirs melts away after a few seconds is a cop out IMHO.
And if these games were
only being released on PC, then maybe you'd have a point. However, they aren't. The engines for these games are designed around the consoles first and foremost, and so they need to be more efficient when it comes to memory usage.
Load up Far Cry 3 and Metro Last Light if you have these games and check the RAM usage. You will be shocked at how little memory these games use.
The anemic memory of both the Xbox 360 and the PS3 has forced game developers to become wizards at the art of memory efficiency in games.
Mafia 2 does not use PhysX to do the car driving physics, that is done on the CPU.
PhysX is both CPU and GPU. There is no discernible difference between the two other than the code path they use, and the performance level. You can run Mafia 2 with PhysX on high on your CPU in fact, although it will struggle mightily with the extremely high particle count and the amount of computations of course...
Arma 3 does not use GPU PhysX and again the CPU PhysX does not do the actual FMs or DMs. I stress that I am not claiming what PhysX can't do in games, I am pointing out what it doesn't do in games
Arma 3 uses PhysX period. Whether it runs on the CPU or the GPU is a non issue because as I said above, PhysX runs on both. GPU acceleration is typically used for more intensive physics effects that would make the CPU struggle and compromise game performance.
Also, what makes you think PhysX isn't doing the FMs or DMs? Especially when the Arma 3 wiki page says:
Physics enabled vehicle handling and environmental objects (PhysX 3)
Source
Potential means nothing if it is not realised. To date PhysX has not reached whatever potential it may have, and it never will because it is proprietary.
You really need to look up what the word proprietary means.. And while PhysX hasn't reached it's full potential, it's on the way to doing so as more and more effects that were never even possible on the CPU become achievable.
Yes. Every single flight sim uses a simulation of fluid dynamics to do the flight models.
I should have been more specific. I really meant liquids..
The problem is that none of what you mention requires a GPU to do the computing. In the context of PC gaming directcompute and OpenCL are non-proprietary as they are open to all platforms used in a current Windows OS.
They require a GPU if you don't want to sacrifice performance and accuracy.
DirectCompute isn't an open standard and is proprietary because it's owned by Microsoft. OpenCL isn't proprietary though, as it's an open standard.