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
A Quick Refresher on the RV770
As Cypress is a direct evolution of the RV770 design, before we talk about what’s new with Cypress we are going to go over a quick rehash of RV770’s internal workings. As it’s necessary to understand how RV770 was built to understand what Cypress changes, if you’re completely unfamiliar with RV770, please take a look at our expanded discussion of RV770 from last year. For the rest of you, let’s get started.
At the center of the RV770 is the Stream Processing Unit (SPU), a single arithmetic logic unit. The RV770 has 800 of these, and they are packaged together in groups of 5 and are what we call a Streaming Processor (SP). A SP contains a register file, a branch predictor, and the aforementioned 5 SPUs, with the 5th SPU being a more complex unit capable of transcendental functions along with the base functions of an ALU. The SP is the smallest unit that can do individual work; every SPU in an SP must execute the same instruction.
For every 16 SPs, AMD groups them together with texture units, L1 cache, shared memory, and controlling logic. This combined block is what AMD calls a SIMD, and RV770 has 10 of them. These 10 SIMDs form the core computational power of the RV770, and in the chip work with various specialized units such as ROPs, rasterizers, L2 cache, and tesselators to form a complete chip.
To utilize the computational power of the hardware, instruction threads are issued to the SPs. These threads are grouped into wavefronts, where there are 64 threads per wavefront. To maximize the utilization of the GPU, threads need to be organized so that they can feed all 5 SPUs in a SP an instruction every clock cycle. Doing this requires extracting instruction level parallelism (ILP) out of programs being passed to the GPU, which is difficult task of AMD’s compiler.
If SPUs go unused, then the performance of the chip suffers due to underutilization. This design gives AMD a great deal of theoretical computational power, but it is always a challenge to fully exploit it.
Facebook
Twitter
RSS
327 Comments
View All Comments
ilnot1 - Wednesday, September 23, 2009 - link
In fact, going by the lowest Newegg prices, this is how the top setups would stack up today:5870 CF .......= $760
GTX 285 SLI .= $592
GTX 295 .......= $470
GTX 275 SLI .= $420
5870 ............= $380
4890 CF ........= $360
4870 X2 ........= $330
This would make the 4890 CF or the 275 SLI setups the best value. And yes I realize there will be availability issues and price adjustments over the next month or so.
DominionSeraph - Thursday, September 24, 2009 - link
you forgot:4870 CF: $260-280
and how about the $180 4850 CF, which is probably the best price/performance for sub-1920x1200 gaming. http://www.anandtech.com/video/showdoc.aspx?i=3517...">http://www.anandtech.com/video/showdoc.aspx?i=3517... You can even get 1GB versions for ~$190.
ilnot1 - Wednesday, September 23, 2009 - link
Another very good review, thanks.But piggy backing on what wicko said, I'm surprised you didn't include two 4890 in CF. Seeing as how you can get two 4890 for less than a 5870 (whenever they are actually available). $180 x 2 = $360 < $379. And this from Newegg, not some super special sale price.
http://www.newegg.com/Product/Product.aspx?Item=N8...">http://www.newegg.com/Product/Product.aspx?Item=N8...
Ryan Smith - Wednesday, September 23, 2009 - link
It's something we would have included if we had the cards. I don't have 2 4890s, and we couldn't get a second one in time.AnotherGuy - Wednesday, September 23, 2009 - link
as always anandtech roxnbjsl2000 - Wednesday, September 23, 2009 - link
Finally time to upgrade..SiliconDoc - Wednesday, September 23, 2009 - link
Not only all that, but when there were 13 big titles for PhysX and a hundred smaller ones, we were told here, "Meh", who needs it.Now, we have a papery and unavailable (egg)except by pre-order(tiger) 5870 launch, a not-existing 5850, with guess what ? NO DX11 games!
Oh wait, there is actually just ONE - see page 7 of review. LOL
---
Conclusion ?: " It looks like NO(err.. just one) DX11 games ready, so... it also looks like NVidia is launching at the right time, and ATI blew their dry unimpressive wad on a piece of paper porn. "
---
Gee no one crowing about the first DX11 card... imagine that...
Good thing , too, considering how 13 big or a hundred titles small of PhysX enhanced games was "nothing to change one's purchase decision over". At least Anand got addicted to Mirror's Edge with PhysX enabled before concluding in the article "meh" this PhysX thing is ok if you like this game, but who cares...
---
Now we have the DX11 pre DX11 games launch with a paper product, so crowing about it wouldn't be too fitting, huh.
monomer - Wednesday, September 23, 2009 - link
Why would a developer would release a DX11 game before DX11 is even available?SiliconDoc - Friday, September 25, 2009 - link
Why would a developer release a DX11 card before DX11 is even available ?(I suppose you'll have to unscrew your hate nvidia foil cap, and grind in the red spikes in it's place to answer that one.)
However, allow me, instead.
1.I have been running windows 7 32&64 for quite some time now, not sure why you haven't been.
2. Battleforge, an ATI promo game, as noted in the review, has released their DX11 patch, hence, with W7 from MSFT (the beta+ free trial good till March 1st 2010 or something like that) I believe any gamer has had a reasonable chance to preview DX11.
---
So anyway...
cactusdog - Friday, September 25, 2009 - link
Ya , ATI has done it again. Excellent performance for a fair price. If Nvidia released this exact card it would be $150-$200 more expensive.LOL, Nvidia sales are gonna be slow for a while.