What happens when you run a PhysX (NVIDIA) optimized game on a AMD video card?

[aka1nas]

Actually in the context of this debate (about which card would run them better) you should lump in the non hardware accelerated physx games with the havok games and compare them to the hardware physx ones.

So about 600:16

That would be fair for the original question in the thread, though not for the Havok vs PhysX argument that the previous poster was trying to frame it as.

 

[Artista]

@Artista you seem to be fishing for negative remarks of amd cards.

Read me completely wrong. If I was fishing for bad remarks for amd cards I would have started a thread called

"Why do amd cards suck so bad compared to the highest glory and honor of the world beating, Galactus stomping, eternity dominating, spiderman squashing, hulk busting, NVIDIA cards?" :biggrin:

Actually I just don't quite grasp it, the whole this game optimized for this such and such card, etc. etc. (Forget only FPS and include other factors)

Like... does amd pay developers to make games favorable to their cards? (which nvidia does so...healthy competition or just dirty pool?)

Is having PhysX give you something that perhaps we could use in someway?

If a game uses PhysX does that mean the game physics and realism will be better than if it was played on a amd (non-physX) card?

So a better or another (more correct?) question could be, which physics engine is better? I guess one engine, in less number of games uses PhysX (off loads some physics to gpu) and the other (Havok?) uses the CPU mainly and what ever GPU is there?

I get some of it...getting back into hardware and learning what you need to know for knowledge sake and for making buying decisions is tough. Mainly though I like to understand, not just buy something blindly. Learning is great.

It seems to be like a discussion in philosophy. No single truth.:\

 

[DaveSimmons]

Most physics is done in software, with Havok much more than the software version of Physx. Using a software library and the CPU means that you write it once and use it on PS3, 360, PCs and maybe even Macs.

That's worked very well but has limits on how much physics you can do at once: a body flopping down a hill is easy, but 500 scraps of paper using physics-based movement instead of a hacked script takes too much away from all of the other game code running on the CPU.

Hardware-based PhysX added to those 16 games has mostly been used for icing on the cake: fluttering papers in Batman, shattering bits of glass in Mirror's Edge, swirling leaves in another game. Just a little extra eye candy in the game.

It's probably going to stay that way because if your game needs hardware PhysX to be played properly, if it's something crucial, then you can't run that game on any PS3 or 360 or on (guessing) 80% the gaming PCs. (Just because a gamer has a nvidia card doesn't mean it's fast enough to do 3D and PhysX well at the same time.)

So the potential market for your game has dropped down to almost nothing. Does that make business sense? No, it doesn't.

 

[Artista]

Most physics is done in software, with Havok much more than the software version of Physx. Using a software library and the CPU means that you write it once and use it on PS3, 360, PCs and maybe even Macs.

That's worked very well but has limits on how much physics you can do at once: a body flopping down a hill is easy, but 500 scraps of paper using physics-based movement instead of a hacked script takes too much away from all of the other game code running on the CPU.

Hardware-based PhysX added to those 16 games has mostly been used for icing on the cake: fluttering papers in Batman, shattering bits of glass in Mirror's Edge, swirling leaves in another game. Just a little extra eye candy in the game.

It's probably going to stay that way because if your game needs hardware PhysX to be played properly, if it's something crucial, then you can't run that game on any PS3 or 360 or on (guessing) 80% the gaming PCs. (Just because a gamer has a nvidia card doesn't mean it's fast enough to do 3D and PhysX well at the same time.)

So the potential market for your game has dropped down to almost nothing. Does that make business sense? No, it doesn't.

That makes sense. I was thinking myself that it was like icing on the cake. If everything else is equal then getting a PhysX card would be best because it runs all Havok games, all other games engines plus with the right game (limited) you get some hardware (gpu) assisted Physics. Like the swirling leaves etc. I like it when you see things like that and hair flowing naturally or wrinkles in face moving, etc. (nice extras)

 

[WelshBloke]

That makes sense. I was thinking myself that it was like icing on the cake. If everything else is equal then getting a PhysX card would be best because it runs all Havok games, all other games engines plus with the right game (limited) you get some hardware (gpu) assisted Physics. Like the swirling leaves etc. I like it when you see things like that and hair flowing naturally or wrinkles in face moving, etc. (nice extras)

It never is though.

 

[DaveSimmons]

That makes sense. I was thinking myself that it was like icing on the cake. If everything else is equal then getting a PhysX card would be best because it runs all Havok games, all other games engines plus with the right game (limited) you get some hardware (gpu) assisted Physics. Like the swirling leaves etc. I like it when you see things like that and hair flowing naturally or wrinkles in face moving, etc. (nice extras)

You do have to spend more money for that though. AMD and nvidia offer similar price/performance so if you need to spend $180 for a card that's fast enough for your 3D needs, you might have to buy a $250 nvidia card to do that same 3D plus the hardware PhysX at the same time.

Unless you already have a good enough nvidia card on hand that you can keep and use as a second card just for PhysX. But then you lose the money you'd get from selling that card.

 

[Artista]

You do have to spend more money for that though. AMD and nvidia offer similar price/performance so if you need to spend $180 for a card that's fast enough for your 3D needs, you might have to buy a $250 nvidia card to do that same 3D plus the hardware PhysX at the same time.

Unless you already have a good enough nvidia card on hand that you can keep and use as a second card just for PhysX. But then you lose the money you'd get from selling that card.

True. I do have my current NVIDIA card, which is a evga 8800GT. I dont know if that is quick enough. I did see the original aegia PhysX card (PCI) online for sale at around ~$35 american dollars.

The nvidia GTX 560Ti seems to rock and coupled with a lower end nvidia card like a 8800gt or other newer lower end card on shellshocker would work.

The best would be a AMD 6950, on sale, unlocked to a 6970 after flash, and paired with a newer low end nvidia card to do PhysX.

I have read it can be done (AMD and nvidia) but takes a hack that doesnt always work.

Edit: Here is a article about PhysX, nvidia, amd and combinations of the two. Its a good read.

http://www.tomshardware.com/reviews/nvidia-physx-hack-amd-radeon,2764.html