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bit-tech revists PhysX in UT3

bit-tech revists PhysX in UT3

The PhysX card used to review UT3 has proven to be faulty, though the card has since been replaced.

This isn't a news story as such, but more of an update on a review we did a little while ago.

Back at the end of last year, we reviewed the phenomenal Unreal Tournament 3, with a page of our extensive review focusing on the Ageia PhysX content which is supported through the game. We took a very close look at the two PhysX-accelerated levels which Ageia has helped design to create scenarios which fully showcase the capabilities of the PhysX hardware.

Our impressions of the levels weren't very good. We found the games to have very poor performance, averaging around 7 FPS, and the PhysX content itself failed to mesh with the game world cohesively, in our opinion.

Shortly after the review was published, Ageia contacted us to let us know that there was a bug in the game which meant that the PhysX content may appear to be enabled, when in fact it isn't. Ageia was content with of our personal opinions of the PhysX content, but was concerned we were not getting optimum performance. In an effort to bring our readers the most honest, reliable and up-to-date content, we agreed to have a second look at the game - but were unable to find out why the performance was so low.

Ageia and bit-tech continued to look into the matter, adding updates to the original article when needed. Things were inevitably delayed a little over the Christmas and New Year period, but we eventually tracked the problem down to the hardware itself. Components of any type can only take so much stress and it seemed that at some point over its lifetime, our PPU reached the limit and failed. Thankfully, Ageia sent us a new card and we were ready to resume our investigation.

We set up a new system to test to the game in, one with proven hardware which matched the recommended system specs for the PhysX levels, installed the PhysX card and had another look at Unreal Tournament 3. This time round the performance was dramatically improved and the framerates increased to a smoother 25 - 30 FPS, though still with occasional stuttering.

The actual PhysX effects however still looked the same and the look of the game matched our previous opinions;

"Firing three rockets into the planks would often only damage the single plank directly hit, not the planks all around it...if you did hit the plank then the debris which came out was always odd looking. It was all small bits, oddly coloured to be slightly lighter than the surroundings and there was always far, far too many of them."

However, what had previously been said about the performance of the game was now revealed not to be a problem with the PhysX hardware itself, but with the specific card we were using. The faulty card is now sitting in an electro-static bag on my desk as I write this, ready to be discarded. The new card is the one which we shall use in all PhysX reviews going forward as we continue to bring readers our honest and complete thoughts on the games we play.

Here at bit-tech we always encourage developers and manufacturers to enter into dialogues with their users and we always try to bring the most honest and reliable articles to our readers. As such, the original UT3 article will remain as it is in order to communicate the process we went through in the review and to let readers know our full opinions. It will however be updated once more with a link to this story, in order to correct the mistakes made when judging the performance of the game.

If you have any questions or comments on the matter, or simply want to let us know how your PhysX card is holding up, then head to the forums and tell the world.

12 Comments

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Zurechial 18th January 2008, 12:27 Quote
That's fair enough. :)

Still can't see myself buying a PhysX card any time soon, though - There's just no appeal.
cjoyce1980 18th January 2008, 12:54 Quote
not sure why this isn't apart of a card, like a sub-processor. I would by a HD3870 with PhysX, but not just a PhysX card
TreeDude 18th January 2008, 13:04 Quote
Shouldn't need to be part of a graphics card. We have quad-core processors. Just take 1 core and dedicate it to physics. Problem solved. If you have a dual core you should be able to decide if the game uses both cores or 1 core and you get the advance physics processed on the other. Physics cards should be dead already.
E.E.L. Ambiense 18th January 2008, 14:23 Quote
I would buy a card, but the price would have to hit a sweet spot in order to do so. It's just not economically feasible to do so at this current moment.
Jamie 18th January 2008, 14:42 Quote
Quote:
Originally Posted by TreeDude
Shouldn't need to be part of a graphics card. We have quad-core processors. Just take 1 core and dedicate it to physics. Problem solved. If you have a dual core you should be able to decide if the game uses both cores or 1 core and you get the advance physics processed on the other. Physics cards should be dead already.

A CPU is a generic data processing machine. It is designed to work on many sizes and types of data. The PPU in a PhysX card would be designed for a particular purpose and as such be much better at that job. If your argument were to be correct we wouldn't need a graphics card. Just dedicate one of the CPU cores to graphics. The same counter argument stands -- a GPU is specifically designed to do a job which is much faster than any CPU at doing the same job.
shadeygrey 19th January 2008, 17:12 Quote
One core on a CPU for graphics? maybe one for PPU? two for everything else? Wouldnt be suprised if we had these chips in 12 months (thinking Nehalem)
mrplow 19th January 2008, 18:03 Quote
Quote:
Originally Posted by Jamie
A CPU is a generic data processing machine. It is designed to work on many sizes and types of data. The PPU in a PhysX card would be designed for a particular purpose and as such be much better at that job. If your argument were to be correct we wouldn't need a graphics card. Just dedicate one of the CPU cores to graphics. The same counter argument stands -- a GPU is specifically designed to do a job which is much faster than any CPU at doing the same job.

Well, a processor just does sums, right? There is no difference at base level between drawing a person and working out where his shot off arm will fly, it's just maths in the end. Piling only physics calculations into a processor will give only physics 'answers'. That's why a 'physics processor' can do so many sums so quickly, because it has nothing else to do*

If a processor is fast enough that it can have a redundant core while playing a game, then that core could do the physics calculations. Indeed, if the thing was hugely powerful, you could have a core dedicated to graphics processing. It's the same deal as putting graphics or physics processors on the PCI-E bus. Put them inside the CPU package and you eliminate that bus so potentially it's much faster, but I guess that's probably a way off.



I'm pretty surprised they are still clinging to this product and trying to get us to buy them. Back in the day when I ran a 386, we got a co-processor to help with the sums in CAD and I'll be honest it flew.

Now, with CPUs as fast as they are and graphics card as ridiculously powerful, I think trying to re-light the co-processor market (which this effectively is) seems like madness.



* admittedly the data might be arranged and delivered in a more favourable manner by some other technical wizardry and little magic chips, but that'd be doable inside a cpu if someone really wanted to.
Tim S 19th January 2008, 18:48 Quote
Quote:
Originally Posted by shadeygrey
One core on a CPU for graphics? maybe one for PPU? two for everything else? Wouldnt be suprised if we had these chips in 12 months (thinking Nehalem)

Well, Intel's got Larrabee coming at some point in the future (it's probably less than 12-18 months away, max)... that's a many core architecture using IA and I wouldn't be surprised if, given Intel's acquisition of Havok, Intel started using some of those cores for physics. After all, Intel has already demoed vortices and other physics in Alan Wake using a first-gen quad-core chip. By the time that game ships, the physics will be pretty damn fast on whatever the fastest Intel processor is then.

Welcome to the forums. :)
Tyinsar 20th January 2008, 05:04 Quote
Quote:
Originally Posted by mrplow
...I'm pretty surprised they are still clinging to this product and trying to get us to buy them. Back in the day when I ran a 386, we got a co-processor to help with the sums in CAD and I'll be honest it flew.

Now, with CPUs as fast as they are and graphics card as ridiculously powerful, I think trying to re-light the co-processor market (which this effectively is) seems like madness.
I'm with Jamie on this. Those co-processors didn't go away at all - they just got integrated. You'll notice that sometimes CPU benchmarks are broken up into ALU & FPU scores. (Read the links provided if you doubt.)
Cupboard 20th January 2008, 17:25 Quote
Interesting that your PPU had failed, its not like you have use it that much. I would be furious if my graphics card died after 1-2 years of light use (that said, my motherboard did :()
metarinka 21st January 2008, 02:31 Quote
jamie is 100% right, I'm not a fan of add-in hardware based physics solutions, but that doesn't mean a General purpose processing would be nearly efficient at the calculations that a dedicated hardware solution would be. It's the same for graphics cards, with dedicated hardware, drivers and algorithmns for the specific task. you also must remember that a physx card is running an optimized physics engine designed to work well with those cards. there really is no competition

the same goes for sound cards and graphics cards. Yes general purpose CPU's are speeding up and having increasing cores, however a dedicated hardware solution that is meant to specifically handle a certain type of calculation can be more focused and optimized as opposed to a CPU which has to handle everything imaginable.
cloudew 28th June 2008, 11:01 Quote
Regards sound cards, the amount of parallel computations needed for that task are far fewer than realtime lighting & physics interactions. So the same does not apply to sound cards to the same extent.
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