What is PhysX and how does it work?

[terrytek]

I am wondering, what is PhysX, how does it work, and what hardware supports it? I am a newbie to this video card technology. I am planning to do a GTX 780 in SLI and a Galaxy Geforce GT610. If PhysX has any performance benefit, I might as well utilize this technology because I only have one other computer with PCIe and that one does not work that hard.

 

Kudos,

 

terrytek

[WoodenMarker]

The 780's would be better for PhysX than the GT 610.

[CoolBeans]

It adds stuff like particle effects (I believe). Only Nvidea cards support it. That will either A. give you less performance or B. Give you no more performance.

[Mr. Expert]

What games do you pay ? Do they even have advanced GPU accelerated Physx ?

[Matman24]

Whatever you do, don't use the GT610 for PhysX. It will be much too slow, and will significantly reduce performance.

The 780's would be more than capable of running PhysX. Hell, even CPU PhysX would run better than on such a low-end card. 

[Hazy125]

It's a real time physics engine that is proprietary for nVidia at the moment

[Bluejay0]

I have a GT610. DO NOT BUY IT. EVER!!!!!!!!

[coen113]

It adds stuff like particle effects (I believe). Only Nvidea cards support it. That will either A. give you less performance or B. Give you no more performance.

that is not completely true, only NVidea cards support advanced physx, AMD just suppords general physx

[coen113]

I have a GT610. DO NOT BUY IT. EVER!!!!!!!!

i have a 630 laying on my shelf somewhere, its pretty good, i got a solid 20 fps on far cry 3 on minimal with it.

[Hazy125]

that is not completely true, only NVidea cards support advanced physx, AMD just suppords general physx

Yeah, and people were complaining that the gt610 had bad PhysX

[coen113]

Yeah, and people were complaining that the gt610 had bad PhysX

the gt 610 is a bad card. no way of getting around that.

[ALXAndy]

The 610 is a multimedia card.

 

Physx is a PPU (Physics processing unit) that is now built into the core of pretty much all (I haven't checked) Nvidia GPUs. It started out life designed and implemented by a company called Ageia. They sold it as a stand alone card (PCI first then PCIE later) that complimented your GPU and ran physics calculations.

 

So basically particles, smashed pieces of glass etc (you get the general idea).

 

Back when it launched it worked perfectly along side ATI (now AMD) GPUs. Nvidia however saw it as some sort of killer app and decided to buy out Ageia.

 

Since then they have pretty much put it on all of their gaming GPUs. It isn't just software it exists as the PPU it always was on your GPU core (it's simply been integrated).

 

Physx titles are quite rare, but, there is no denying that it definitely adds to a game. Sadly like many other technologies like it (like the Hydra chips that allowed mixed SLI or Crossfire) practically no game developers support it as it means extra work and then you pretty much make your game appeal to half of the market.

 

There are ways to run a secondary Nvidia GPU and enable it to run as the PPU but this requires a hack by Gen L. Otherwise it is blocked in the drivers..

 

Sadly it's not used much. The best instance of it was Mirror's Edge which IMO definitely feels like it's missing something without it. It was also good in the Batman games where it added smoke and broken small objects, and made quite a difference in Mafia 2.

 

It's not a must have, but, when it works it does work well

[Godlygamer23]

PhysX is a physics processing engine orignially by Ageia. They had the PPU which stood for Physics Processing Unit. NVIDIA bought them out and integrated PhysX into their cards. PhysX adds things like cloth, particle, and smoke effects. Games like Borderlands 2 and Batman Arkham Asylum showcase what PhysX is capable of. On systems with AMD video cards, PhysX gets thrown on the CPU at all times. This can result in a lower frame rate as well as less spectacular PhysX effects. Years ago, it used to be possible to pair an AMD card with an NVIDIA card and make the NVIDIA card process PhysX only. However, NVIDIA caught that and updated their drivers to not allow that.

[Viking Kong]

I've seen Borderlands 2  side by side comparisons with and without PhysX, as well as Batman Arkham City. I suggest you look them up on youtube, that way you can see what it adds to the game.

[Signex]

Ugh, i'll miss PhysX so much now i've got a ATI card.

[mgsstar]

I would not get the GT610 since the GTX 780 would be better in Physx and wouldn't need a dedicated Physx card because it would be enough imo. Physx basically a physics engine and it adds particles and effects to make the game more realistic to gamers. Here are some videos of Physx demos and comparing the graphics with and without physx:

 

[terrytek]

Well, I already have a Galaxy GT610 OC and I don't want to waste 30 bucks letting it sit around. So, what you guys are all saying, is , NEVER do it?

[Godlygamer23]

Basically, it's not recommended to use it as a dedicated PhysX card. It won't necessarily increase performance and may actually decrease performance.

[Kuzma]

If you read my APUs and the future of computing thread (found in my PM) I briefly go over what it does .

[Cyberpunk177]

Dude just no. Forget you own the GT610. Physx does make a huge difference. It's not implemented in a lot of games. The most recent game i played that uses physx effects is Metro Last Light,and to be honest with you,it really increases immersion.(Everything just feels so real). The other game i played that supports it is Mafia 2. It was also very good to have it enabled. The most noticeable difference was in games like Warframe and Hawken to name but a few. Here's some video links to show you the comparisons.

 

Make sure you look at all of them as all the physics technologies have different effects on different games,and hence affect immersion in different ways.

 

http://www.youtube.com/watch?v=9_UNRp7Wrog

 

http://www.youtube.com/watch?v=EWFkDrKvBRU

 

http://www.youtube.com/watch?v=w0xRJt8rcmY
 

http://www.youtube.com/watch?v=QKa8pxMCPw0

 

http://www.youtube.com/watch?v=pIn3NoMgxgo

 

http://www.youtube.com/watch?v=vJClNPiyOYQ

 

http://www.youtube.com/watch?v=PAlC3VSN4Ks

 

http://www.youtube.com/watch?v=qaeXz8FJwm4

 

http://www.youtube.com/watch?v=0v1NgyzQ9tM

 

http://www.youtube.com/watch?v=j89kwKfYf5w

 

If you're worried about the performance hit when it's enabled,i got just the solution for you. Go to the control panel>Physx options tab>change default physx processor to GPU and not auto select....You'll thank me later.

 

@ALXAndy did a good summary of it above,make sure you give it a read.

 

Why you shouldn't use a dedicated GPU for physx

http://www.youtube.com/watch?v=cbww3dhzK0M

 

Remember,lots of information is always better,as you make a wiser decision.

[ALXAndy]

Well, I already have a Galaxy GT610 OC and I don't want to waste 30 bucks letting it sit around. So, what you guys are all saying, is , NEVER do it?

 

I mean yeah, give it a go if you're bored. However I did some research a few years back and running an under powered GPU for Physx was worse than making my CPU take care of it. Apparently Physx would be easily ran by the CPU if it were optimised for it, but, it's not. So off loading it to your CPU makes it crawl. I'm not sure about the truth in that but Havok seems to do the trick without needing a PPU.

 

Any way as I said, give it a try. Just know that if it doesn't work well it won't be worth using. I tried it once with an onboard Nvidia GPU and it brought my frames down into the single digits.

 

As an example for Batman Arkham Asylum (not City) you need at least a dedicated (IE seperate) GTS 250. Which is pretty much a 9800 GTX or 8800 Ultra.

[Godlygamer23]

I mean yeah, give it a go if you're bored. However I did some research a few years back and running an under powered GPU for Physx was worse than making my CPU take care of it. Apparently Physx would be easily ran by the CPU if it were optimised for it, but, it's not. So off loading it to your CPU makes it crawl. I'm not sure about the truth in that but Havok seems to do the trick without needing a PPU.

In some games, the CPU is better at doing it. Sometimes in games that support PhysX, the CPU handles it(with it on Auto select in the drivers). It also depends on the implementation. In games like Batman Arkham City, your frame rate dramatically goes down whether it's on the CPU or GPU.