Guru3D: PhysX by NVIDIA - A review of what's to come next week ...

[twobombs]

Originally Posted by Hilbert Hagedoorn

No mate.

These cards are EOL, won't be sold much longer nobody buys them and this is why they are still available (look at the BFG offering, it's already EOL), + they are more expensive than a GeForce 9600 GT. Fact is that a 9600GT has much more horsepower and stamina than one Ageia card.

Please, forget about the Ageia cards. In the end support for them will be killed off as well.

Yeah. Right. Wattage, performance, or is that too 2007 ?

http://www.computerbase.de/artikel/h...ueberblick/12/
Mit einer schnelleren Grafikkarte wie einer GeForce 9600 GT erreicht man schon die Performance einer GeForce GTX 280 kombiniert mit der Ageia-PhysX-Karte und kann so sämtliche PhysX-Anwendungen flüssig wiedergeben.

[andries]

If I dedicate a second gpu for physx, lets say a gtx280. What would the performance difference be against a 8600gt in the same situation. Would both cards deliver the same performance under physx? Or would a faster gpu = faster and better physx?

[fhertlein]

Impact of TRI sli switching to regular SLI and using the third card as dedicated Physx?

[sava700]

Originally Posted by Hilbert Hagedoorn

At this time yes, you'd need a second cable connected. NVIDIA however is trying to get that fixed and more user-friendly.

When this is done I'll grab another card..either higher or the same one and do this...but now the cable situation along with fresh out the gates it prob isn't worth the headache..not to mention I'm not really playing any games with PhysX enabled at this point.

Great article though!

[bLinkZor]

This is what I came across SLI forums.
I posted the same in the NVIDIA videocard section.

Question: Which graphics cards can accelerate NVIDIA PhysX?
A: All GeForce 8, 9, and GTX 200 series graphics cards with at least 256MB of local onboard graphics memory will be able to accelerate NVIDIA PhysX.

Question: Do you support PhysX on SLI now?
A: Running PhysX in SLI performance mode (SLI on), where each GPU renders a separate frame that includes both graphics and physics workloads, is supported in our August Release 177 drivers, but it’s still a work in progress. Our initial focus with these drivers is to either use a single GPU to run graphics and physics, or run graphics on one GPU and physics on a second GPU. The latter “multi-GPU” configuration currently has a limitation under Vista (not XP) that requires a monitor attached to each GPU (extending the desktop to the second monitor), or a monitor cable attached to both GPUs and connected to a single monitor. Future drivers will remove this limitation.

Question: How will PhysX scale from single card to 2-way and 3-way SLI in the future?
A: PhysX will support multi-GPU setups. Future drivers will deliver better performance and user experiences.

Question: Can I run PhysX on a different card than the one I use for gaming? When will you release support for asymmetrical multi-GPU configurations?
A: Yes. PhysX will support asymmetric multi-GPU configurations within the next few months. There is some limited Beta support in the first release, but the support will improve in future releases. This will enable users to still use their older 8 or 9-Series card when they upgrade to a newer card based on the GeForce GTX 280 for example.

Question: Can I run PhysX on my motherboard GPU?
A: PhysX uses NVIDIA CUDA technology, so if the motherboard GPU supports CUDA, then it can be used for PhysX. Generally running both graphics and PhysX on a motherboard GPU may not deliver the best experience; adding a discrete GeForce GPU significantly improves performance.

Question: Does PhysX scale across the GPU and CPU? If yes, does that mean having a faster CPU enhances PhysX performance or visual quality?
A: PhysX uses both the CPU and GPU, but generally the most computationally intensive operations are done on the GPU. A CPU upgrade could result in some performance improvement, as would a GPU upgrade, but the relative improvement is very dependent on the initial balance of the system. An optimized PC with the right mix of CPU to GPU horsepower will be the best balanced solution.

Question: How does PhysX support heterogeneous computing?
A: PhysX shows how heterogeneous computing delivers the best user experience. While the game is running, the PhysX system executes portions of the physical simulation on the CPU and other portions on the parallel processors of the GPU. This ensures all the components of a balanced PC are used efficiently to deliver the best experience.

Question: Why do some PhysX demos only run on one CPU core?
A: PhysX fully supports applications which are multi-threaded to leverage multiple CPU cores. Some single-feature PhysX demos consist of only one type of physics body which runs more efficiently on a single CPU core. If the same demo was part of a more complete game environment, there would be multiple PhysX objects and active game and rendering threads, so the game would leverage more than one CPU core more efficiently. Improving the way individual PhysX objects can be efficiently spread over multi-processors is being actively researched and developed.

Question: Will running PhysX on a GPU slow down gaming performance?
A: Running physics on the GPU is typically significantly faster than running physics on the CPU, so overall game performance is improved and frame rates can be much faster. However, adding physics can also impact performance in much the same way that anti-aliasing impacts performance. Gamers always enable AA modes if they can because AA makes the game look better. Gamers will similarly enable physics on their GPUs so long as frame rates remain playable. With AA enabled, running physics on a GPU will generally be much faster than running physics on a CPU when AA is enabled. PhysX running on a dedicated GPU allows offloading the PhysX processing from the GPU used for standard graphics rendering, resulting in an optimal usage of processing capabilities in a system.

Question: Intel and AMD say it’s better to run physics on the CPU. What is NVIDIA’s position?
A: PhysX runs faster and will deliver more realism by running on the GPU. Running PhysX on a mid-to-high-end GeForce GPU will enable 10-20 times more effects and visual fidelity than physics running on a high-end CPU. Portions of PhysX processing actually run on both the CPU and GPU, leveraging the best of both architectures to deliver the best experience to the user. More importantly, PhysX can scale with the GPU hardware inside your PC. Intel and AMD solutions, which utilize the Havok API, are fixed function only and cannot scale.

Source

[Nuke_Meltdown]

Nice PSU bLinkZor...1650W!

Where did you get that???....

[scatman839]

It's 1200w and a 450w addon thing.

[Nuke_Meltdown]

Wow! I wouldn't like to get your electricity bill.....When you played 4H/Day the whole month....Especially if you wanna build a TRI-SLI or something like that.

At least its future proof!

Back to the subject...Now that the PhysX can be easily handled by the GPU, it would be great to see a lot of new game with PhysX engine.....

[vhon05]

based on the GRAW2 chart, does that actually say that the game runs better without physx?

[puffpirat]

Yes!

I like the comparison with AA. You get kinda more "eye candy" but pay with lower framerates...anything else would be like a perpetuum mobile

[Quark Fusion]

It's same as running game without Antialiasing and Anisotropy filtering with low detail — you get better FPS, but worse image quality.

And one more note that not mentoined in article: your LCD monitor can't show more that 60 frames per second and if you enable vsync to avoid 2 parts of different frames on screen at once (do you preffer half of screen effect at 120 fps to full one at 60?) you may have some spare GPU power for using in physics calculations

[bozotheclown]

This "SLI mode - have two GPUs render both Graphics + PhysX." is in the same review

I don't notice a performance drop in UT3.

Anyway, it's all very nice but without more good games using PhysX it's all pretty useless

Originally Posted by Barton C++

great, got a couple of physx questions already!


* for starters, physx with single G92 card reduces fps to 66% ? (run UT3)

* SLI'd G92 cards with physx, same fps as with single card w/o physx (the 2nd takes physx part alone) - this seems like a waste for SLI GTX 280 buyers

* Saving up old cards for physx makes the most sense

edit /// soz, should have read the article first..but hey, here is the thread for questions anyhow (spotted the single/sli/multi gpu with physx explanation)

[vhon05]

Originally Posted by Quark Fusion

It's same as running game without Antialiasing and Anisotropy filtering with low detail — you get better FPS, but worse image quality.

And one more note that not mentoined in article: your LCD monitor can't show more that 60 frames per second and if you enable vsync to avoid 2 parts of different frames on screen at once (do you preffer half of screen effect at 120 fps to full one at 60?) you may have some spare GPU power for using in physics calculations

umm...i thought there are no difference in image quality. You're just transferring the physics calculation from your cpu to your gpu if you have the physx drivers. right? that explains the lower framerate since the gpu is being loaded with more load.

[Hilbert Hagedoorn]

Asked yesterday by some users, from NVIDIA:

Q - Will there be an option to run SLI with two cards, and use a 3rd card for PhysX ?

A - Yes, that will be possible for sure. We need to add functionality into the driver in order to support such configs, but it’s already underways

[TDurden]

Situation:

ASUS P5E X38 Motherboard with two PCIE-E 2.0 16x Crossfire ready slots.

First PCI-E 16x slot for a powerful GPU let's say 4870.
Second PCI-E 16x slot for a cheap Geforce 8 or 9 series card just for physics calculations only.

Would it work?

[Scyphe]

Originally Posted by vhon05

umm...i thought there are no difference in image quality. You're just transferring the physics calculation from your cpu to your gpu if you have the physx drivers. right? that explains the lower framerate since the gpu is being loaded with more load.

Uhm, yeah, but the GPU is 10-20 times faster at physics calculations than the CPU so the net effect should give you more and better physics with no noticeable drop in frame rate. However, I have no idea how nVidia allocates stream processors, how many pipes they use, if that's even the way they do it. For all I know they may use 4 SPU's (one quad) for Physx. In my case that would leave me with 108 SPU's since I have 112 of them on my 8800GT. But as I said, I have no idea what they're actually doing.

[puffpirat]

Thx Hilbert!

Let´s see when the drivers make it happen

[Avefenix]

owning a 8800gtx, and thinking in get a 260GTX for Phyxs, so... i have 550W of power supply, what power supply plus would i need for run the 2 cards for Phyxs?

Ah its so greattt!!!

[PoiNt54]

Nice article! Now I wonder with nVidia's recent involvement with CoD4, will we see a PhysX add-on in pack #2 for that game. Doesn't hurt to dream ..

[Quark Fusion]

Originally Posted by vhon05

umm...i thought there are no difference in image quality. You're just transferring the physics calculation from your cpu to your gpu if you have the physx drivers. right? that explains the lower framerate since the gpu is being loaded with more load.

Wrong, in case of higher framerate without PhysX physics laws just doesn't exists — you see less detail and effects. And that explains lower framerate, since game have more to show you. If physics were calculated on CPU your framerates will be much lower and most likely at unplayable level.

[bradleyg5]

Originally Posted by vhon05

umm...i thought there are no difference in image quality. You're just transferring the physics calculation from your cpu to your gpu if you have the physx drivers. right? that explains the lower framerate since the gpu is being loaded with more load.

wrong, certain effects cannot be enabled without a physics card. with Ghost recon you cannot enable the extreme phsyics without a PhysX card. so when you enable PhysX you get more partical effects there is stuff flying threw the air, trees bend with the wind explosions send more objects flying.

enabling the special physX effects will reduce framerates only when there is special gpu/ppu only effects. if you try and enable the effects without a physX enabled card you will see drastically reduced framesrates in the order of sub 10fps since the CPU is not powerfulll enough.

[Barry J]

Great i have used my Old GPU

PCIE slot1 BFG 9800GTX---------Games

PCIE slot2 BFG 8800GTS 512-----PhysX

so i got PhysX working on my 8800GTS 512 and tested in vantage and it works. mmmmmmmm thought i would play a game that uses PhysX but i checked all my games and none use it.

What are the games with Demos that use it so i can have a play

I could google it but would end up downloading a rubbish game

[frizbee]

Originally Posted by Hilbert Hagedoorn

Asked yesterday by some users, from NVIDIA:

Q - Will there be an option to run SLI with two cards, and use a 3rd card for PhysX ?

A - Yes, that will be possible for sure. We need to add functionality into the driver in order to support such configs, but it’s already underways

Thanks for clarifying this. I tried to install my olf 8600GT in the third PCIE slot on my MB and lost SLI and physix support. I took it out and got both back. I guess I'll just have to wait a while to get this to work.

[Copey]

Originally Posted by Barry J

Great i have used my Old GPU

PCIE slot1 BFG 9800GTX---------Games

PCIE slot2 BFG 8800GTS 512-----PhysX

so i got PhysX working on my 8800GTS 512 and tested in vantage and it works. mmmmmmmm thought i would play a game that uses PhysX but i checked all my games and none use it.

What are the games with Demos that use it so i can have a play

I could google it but would end up downloading a rubbish game

Cellfactor : Revolution and Warmonger are probably the 2 best, good fun for abit but needed more support i thought, hopefully with many more people being able to take advantage of physX now there should be some good games that take advantage of the hardware coming out.

EDIT: Switchball is also good fun.

[gamepagol]

if i consider the 2 GPU Solution one for GPU and 2nd for PPU then is it really need to run 2nd GPU for PhysX on x16 PCIe or it can do the same on PCIe x4 or x1 or even a PCI VGA Card can do the trick.

is there any performance degradation for running GPU for PPU in X4 slot instead of X16 PCIe slot?