AMD's Radeon HD 5870: Bringing About the Next Generation Of GPUs
by Ryan Smith on September 23, 2009 9:00 AM EST- Posted in
- GPUs
DirectCompute, OpenCL, and the Future of CAL
As a journalist, GPGPU stuff is one of the more frustrating things to cover. The concept is great, but the execution makes it difficult to accurately cover, exacerbated by the fact that until now AMD and NVIDIA each had separate APIs. OpenCL and DirectCompute will unify things, but software will be slow to arrive.
As it stands, neither AMD nor NVIDIA have a complete OpenCL implementation that's shipping to end-users for Windows or Linux. NVIDIA has OpenCL working on the 8-series and later on Mac OS X Snow Leopard, and AMD has it working under the same OS for the 4800 series, but for obvious reasons we can’t test a 5870 in a Mac. As such it won’t be until later this year that we see either side get OpenCL up and running under Windows. Both NVIDIA and AMD have development versions that they're letting developers play with, and both have submitted implementations to Khronos, so hopefully we’ll have something soon.
It’s also worth noting that OpenCL is based around DirectX 10 hardware, so even after someone finally ships an implementation we’re likely to see a new version in short order. AMD is already talking about OpenCL 1.1, which would add support for the hardware features that they have from DirectX 11, such as append/consume buffers and atomic operations.
DirectCompute is in comparatively better shape. NVIDIA already supports it on their DX10 hardware, and the beta drivers we’re using for the 5870 support it on the 5000 series. The missing link at this point is AMD’s DX10 hardware; even the beta drivers we’re using don’t support it on the 2000, 3000, or 4000 series. From what we hear the final Catalyst 9.10 drivers will deliver this feature.
Going forward, one specific issue for DirectCompute development will be that there are three levels of DirectCompute, derived from DX10 (4.0), DX10.1 (4.1), and DX11 (5.0) hardware. The higher the version the more advanced the features, with DirectCompute 5.0 in particular being a big jump as it’s the first hardware generation designed with DirectCompute in mind. Among other notable differences, it’s the first version to offer double precision floating point support and atomic operations.
AMD is convinced that developers should and will target DirectCompute 5.0 due to its feature set, but we’re not sold on the idea. To say that there’s a “lot” of DX10 hardware out there is a gross understatement, and all of that hardware is capable of supporting at a minimum DirectCompute 4.0. Certainly DirectCompute 5.0 is the better API to use, but the first developers testing the waters may end up starting with DirectCompute 4.0. Releasing something written in DirectCompute 5.0 right now won’t do developers much good at the moment due to the low quantity of hardware out there that can support it.
With that in mind, there’s not much of a software situation to speak about when it comes to DirectCompute right now. Cyberlink demoed a version of PowerDirector using DirectCompute for rendering effects, but it’s the same story as most DX11 games: later this year. For AMD there isn’t as much of an incentive to push non-game software as fast or as hard as DX11 games, so we’re expecting any non-game software utilizing DirectCompute to be slow to materialize.
Given that DirectCompute is the only common GPGPU API that is currently working on both vendors’ cards, we wanted to try to use it as the basis of a proper GPGPU comparison. We did get something that would accomplish the task, unfortunately it was an NVIDIA tech demo. We have decided to run it anyhow as it’s quite literally the only thing we have right now that uses DirectCompute, but please take an appropriately sized quantity of salt – it’s not really a fair test.
NVIDIA’s ocean demo is a fairly simple proof of concept program that uses DirectCompute to run Fast Fourier transforms directly on the GPU for better performance. The FFTs in turn are used to generate the wave data, forming the wave action seen on screen as part of the ocean. This is a DirectCompute 4.0 program, as it’s intended to run on NVIDIA’s DX10 hardware.
The 5870 has no problem running the program, and in spite of whatever home field advantage that may exist for NVIDIA it easily outperforms the GTX 285. Things get a little more crazy once we start using SLI/Crossfire; the 5870 picks up speed, but the GTX 295 ends up being slower than the GTX 285. As it’s only a tech demo this shouldn’t be dwelt on too much beyond the fact that it’s proof that DirectCompute is indeed working on the 5800 series.
Wrapping things up, one of the last GPGPU projects AMD presented at their press event was a GPU implementation of Bullet Physics, an open source physics simulation library. Although they’ll never admit it, AMD is probably getting tired of being beaten over the head by NVIDIA and PhysX; Bullet Physics is AMD’s proof that they can do physics too. However we don’t expect it to go anywhere given its very low penetration in existing games and the amount of trouble NVIDIA has had in getting developers to use anything besides Havok. Our expectations for GPGPU physics remains the same: the unification will come from a middleware vendor selling a commercial physics package. If it’s not Havok, then it will be someone else.
Finally, while AMD is hitting the ground running for OpenCL and DirectCompute, their older APIs are being left behind as AMD has chosen to focus all future efforts on OpenCL and DirectCompute. Brook+, AMD’s high level language, has been put out to pasture as a Sourceforge project. Compute Abstract Layer (CAL) lives on since it’s what AMD’s OpenCL support is built upon, however it’s not going to see any further public development with the interface frozen at the current 1.4 standard. AMD is discouraging any CAL development in favor of OpenCL, although it’s likely the High Performance Computing (HPC) crowd will continue to use it in conjunction with AMD’s FireStream cards to squeeze every bit of performance out of AMD’s hardware.
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SiliconDoc - Monday, September 28, 2009 - link
When the GTX295 still beats the latest ati card, your wish probably won't come true. Not only that, ati's own 4870x2 just recently here promoted as the best value, is a slap in it's face.It's rather difficult to believe all those crossfire promoting red ravers suddenly getting a different religion...
Then we have the no DX11 released yet, and the big, big problem...
NO 5870'S IN THE CHANNELS, reports are it's runs hot and the drivers are beta problematic.
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So, celebrating a red revolution of market share - is only your smart aleck fantasy for now.
LOL - Awwww...
silverblue - Monday, September 28, 2009 - link
It's nearly as fast as a dual GPU solution. I'd say that was impressive.DirectX 11 comes out in less than a month... hardly a wait. It's not as if the card won't do DX9/10.
Hot card? Designed to be that way. If it was a real issue they'd have made the exhaust larger.
Beta problematic drivers? Most ATI launches seem to go that way. They'll be fixed soon enough.
SiliconDoc - Monday, September 28, 2009 - link
Gee, I thought the red rooster said nvidia sales will be low for a while, and I pointed out why they won't be, and you, well you just couldn'r handle that.I'd say a 60.96% increase in a nex gen gpu is "impressive", and that's what Nvidia did just this last time with GT200.
http://www.anandtech.com/video/showdoc.aspx?i=3334...">http://www.anandtech.com/video/showdoc.aspx?i=3334...
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BTW - the 4870 to 4890 move had an additional 3M core transistors, and we were told by you and yours that was not a "rebrand".
BUT - the G80 move to G92 added 73M core transistors, and you couldn't stop shrieking "rebrand".
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nearly as fast= second best
DX11 in a month = not now and too early
hot card -= IT'S OK JUST CLAIM ATI PLANNED ON IT BEING HOT !ROFL, IT'S OK TO LIE ABOUT IT IN REVIEWS, TOO ! COCKA DOODLE DOOO!
beta drivers = ALL ATI LAUNCHES GO THAT WAY, NOT "MOST"
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Now, you can tell smart aleck this is a paper launch like the 4870, the 4770, and now this 5870 and no 5850, becuase....
"YOU'LL PUT YOUR HEAD IN THE SAND AND SCREAM IN CAPS BECAUSE THAT'S HOW YOU ROLL IN RED ROOSERVILLE ! "
(thanks for the composition Jared, it looks just as good here as when you add it to my posts, for "convenience" of course)
ClownPuncher - Monday, September 28, 2009 - link
It would be awesome if you were to stop posting altogether.SiliconDoc - Monday, September 28, 2009 - link
It would be awesome if this 5870 was 60.96% better than the last ati card, but it isn't.JarredWalton - Monday, September 28, 2009 - link
But the 5870 *is* up to 65% faster than the 4890 in the tested games. If you were to compare the GTX 280 to the 9800 GX2, it also wasn't 60% faster. In fact, 9800 GX2 beat the GTX 280 in four out of seven tested games, tied it in one, and only trailed in two games: Enemy Territory (by 13%) and Oblivion (by 3%), making ETQW the only substantial win for the GT200.So we're biased while you're the beacon of impartiality, I suppose, since you didn't intentionally make a comparison similar to comparing apples with cantaloupes. Comparing ATI's new card to their last dual-GPU solution is the way to go, but NVIDIA gets special treatment and we only compare it with their single GPU solution.
If you want the full numbers:
1) On average, the 5870 is 30% faster than the 4890 at 1680x1050, 35% faster at 1920x1200, and 45% faster at 2560x1600.
2) Note that the margin goes *up* as resolution increases, indicating the major bottleneck is not memory bandwidth at anything but 2560x1600 on the 5870.
3) Based on the old article you linked, GTX 280 was on average 5% slower than 9800X2 and 59% faster than the 9800 GTX - the 9800X2 was 6.4% faster than the GTX 280 in the tested titles.
4) Making the same comparisons, 5870 is only 3.4% faster than the 4870X2 in the tested games and 45% faster than the 4890HD.
Now, the games used for testing are completely different, so we have to throw that out. DoW2 is a huge bonus in favor of the 5870 and it scales relatively poorly with CF, hurting the X2. But you're still trying to paint a picture of the 5870 as a terrible disappointment when in fact we could say it essentially equals what NVIDIA did with the GTX 280.
On average, at 2560x1600, if NVIDIA's GT300 were to come out and be 60% faster than the GTX 285, it will beat ATI's 5870 by about 15%. If it's the same price, it's the clear choice... if you're willing to wait a month or two. That's several "ifs" for what amounts to splitting hairs. There is no current game that won't run well on the HD 5870 at 2560x1600, and I suspect that will hold true of the GT300 as well.
(FWIW, Crysis: Warhead is as bad as it gets, and dropping 4xAA will boost performance by at least 25%. It's an outlier, just like Crysis, since the higher settings are too much for anything but the fastest hardware. "High" settings are more than sufficient.)
SiliconDoc - Tuesday, September 29, 2009 - link
In other words, even with your best fudging and whining about games and all the rest, you can't even bring it with all the lies from the 15-30 percent people are claiming up to 60.96%--
Yes, as I thought.
zshift - Thursday, September 24, 2009 - link
My thoughts exactly ;)I knew the 5870 was gonna be great based on the design philosophy that AMD/ATi had with the 4870, but I never thought I'd see anything this impressive. LESS power, with MORE power! (pun intended), and DOUBLE the speed, at that!
Funny thing is, I was actually considering an Nvidia gpu when I saw how impressive PhysX was on Batman AA. But I think I would rather have near double the frame rates compared to seeing extra paper fluffing around here and there (though the scenes with the scarecrow are downright amazing). I'll just have to wait and see how the GT300 series does, seeing as I can't afford any of this right now (but boy, oh boy, is that upgrade bug itching like it never has before).
SiliconDoc - Thursday, September 24, 2009 - link
Fine, but performance per dollar is on the very low end, often the lowest of all the cards. That's why it was omitted here.http://www.techpowerup.com/reviews/ATI/Radeon_HD_5...">http://www.techpowerup.com/reviews/ATI/Radeon_HD_5...
THE LOWEST overall, or darn near it.
erple2 - Friday, September 25, 2009 - link
So what you're saying then is that everyone should buy the 9500 GT and ignore everything else? If that's the most important thing to you, then clearly, that's what you mean.I think that the performance per dollar metrics that are shown are misleading at best and terrible at worst. It does not take into account that any frame rates significantly above your monitor refresh are for all intents and purposes wasted, and any frame rates significantly below 30 should by heavily weighted negatively. I haven't seen how techpowerup does their "performance per dollar" or how (if at all) they weight the FPS numbers in the dollar category.
SLI/Crossfire has always been a lose-lose in the "performance per dollar" category. Curiously, I don't see any of the nvidia SLI cards listed (other than the 295).
That sounds like biased "reporting" on your part.