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
Angle-Independent Anisotropic Filtering At Last
For a number of years now the quality of anisotropic filtering has been slowly improving. Early implementations from AMD and NVIDIA were highly angle-dependent, resulting in a limited improvement to image quality from such filtering. The angle-dependent nature lead to shimmering and other artifacting that was not ideal.
As of the previous generation of cards, the quality of anisotropic filtering had become pretty good. NVIDIA’s best filtering mode was pretty close to angle-independent, and AMD’s only slightly worse. Neither was perfect, but neither was bad either.
The Radeon HD 4890
The GeForce GTX 285
However so long as no one had an angle-independent implementation, there was room to improve. And AMD has gone there. The anisotropic filtering algorithm used by the 5000 series is now truly and completely angle-independent. There are no more filtering tricks being used.
The Radeon HD 5870: Perfection
As you can see, the MIP maps in our venerable D3D AF Tester are perfectly circular, the hallmark of an angle-independent implementation. With angle-independent filtering, this effectively marks the end of the filtering arms race. AMD has won, and should NVIDIA catch up in the future the two would merely be tied. There’s nowhere left to go for quality beyond angle-independent filtering at the moment.
AMD tells us that there is no performance hit with their new algorithm compared to their old one. This is a bit hard to test since we can’t enable the old algorithm on the 5870, but certainly whatever performance hit there is, is similarly minor. In all of the testing we’re doing today, you will see results done with 16x anisotropic filtering used.
What you won’t see however is a difference, particularly with our static screenshots. When discussing the matter, AMD noted that the difference in perceived quality between the old algorithm and the new one was practically the same. After looking at matters we find ourselves in agreement with AMD; we were not able to come up with any situations where there was a noticeable difference, beyond the obvious AF quality tests that are designed to identify such changes.
Regardless of the outcome, AMD deserves kudos for making angle-independent anisotropic filtering happen. It’s demonstrably perfect filtering with no speed hit versus the previous generation of filtering; making it in essence a “free” improvement in image quality, however slight the real-world results are. We’re always ready to get better image quality out of our video cards, after all.
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SiliconDoc - Sunday, September 27, 2009 - link
I'll be watching you for the very same conclusion when NVidia launches soft and paper.I'll bet ten thousand bucks you don't say it.
I'll bet a duplicate amount you're a red rager fan, otherwise YOU'D BE HONEST, NOT HOSTILE !
rennya - Thursday, September 24, 2009 - link
It may be paper-launch in the US, but here somewhere in South East Asia I can already grab a Powercolor 5870 1GB if I so desire. Powercolor is quite aggresive here promoting their ATI 5xxx wares just like Sapphire does when the 4xxx series comes out.SiliconDoc - Thursday, September 24, 2009 - link
I believe you. I've also seen various flavors of cards not available here in the USA, banned by the import export deals and global market and manufacturer and vendor controls and the powers that be, and it doesn't surprise me when it goes the other way.Congratulations on actually having a non fake launch.
Spoelie - Wednesday, September 23, 2009 - link
"The engine allows for complete hardware offload of all H.264, MPEG-2 and VC1 decoding".This has afaik never been true for any previous card of ATi, and I doubt it has been tested to be true this time as well.
I have detailed this problem several times before in the comment section and never got a reply, so I'll summarize: ATi's UVD only decodes level 4 AVC (i.e. bluray) streams, if you have a stream with >4 reference frames, you're out of luck. NVIDIA does not have this limitation.
lopri - Wednesday, September 23, 2009 - link
Yeah and my GTX 280 has to run full throttle (3D frequency) just to play a 720p content and temp climbs the same as if it were a 3D game. Yeah it can decode some *underground* clips from Japan, big deal. Oh and it does that for only H.264. No VC-1 love there. I am sure you'd think that is not a big deal, but the same applies to those funky clips with 13+ reference frames. Not a big deal. Especially when AMD can decode all 3 major codecs effortlessly (performance 2D frequency instead of 3D frequency)rennya - Thursday, September 24, 2009 - link
G98 GPUs (like 8400GS discrete or 9400 chipset) or GT220/G210 can also do MPEG2/VC-1/AVC video decoding.The GPU doesn't have to run full throttle either, as long as you stick to the 18x.xx drivers.
SJD - Wednesday, September 23, 2009 - link
Ryan,Great article, but there is an inconsistancy. You say that thanks to there only being 2 TDMS controllers, you can't use both DVI connectors at the same time as the HDMI output for three displays, but then go onto say later that you can use the DVI(x2), DP and HDMI in any combination to drive 3 displays. Which is correct?
Also, can you play HDCP protected content (a Blu-Ray disc for example) over a panel connected to a Display Port connector?
Otherwise, thanks for the review!
Ryan Smith - Wednesday, September 23, 2009 - link
It's the former that is correct: you can only drive two TDMS devices. The article has been corrected.And DP supports HDCP, so yes, protected content will play over DP.
SJD - Friday, September 25, 2009 - link
Thanks for clarifying that Ryan - It confirms what I thought.. :-)chowmanga - Wednesday, September 23, 2009 - link
I'd like to see a benchmark using an amd cpu. I think it was the Athlon II 620 article that pointed out how Nvidia hardware ran better on AMD cpus and AMD/ATI cards ran better on Intel cpus. It would be interesting to see if the 5870 stacks up against Nv's current gen with other setups.