In 2009-2010, AMD launched the entire 4 chip Evergreen series in 6 months. By previous standards this was a quick pace for a new design, especially since AMD had not previously attempted a 4 chip launch in such a manner. Now in 2012 AMD’s Southern Islands team is hard at work at wrapping up their own launch with new aspirations on quickness. Evergreen may have launched 4 chips in 6 months, but this month AMD will be completing the 3 chip Southern Islands launch in half the time – 3 chips in a mere 3 months.

To that end today AMD is taking the wraps off the final piece of the Southern Islands puzzle: Pitcairn. The middle child of the family, it will be the basis of AMD’s $250+ enthusiast segment Radeon HD 7800 series. We’ve seen AMD capture the high-end with the 7900 series and struggle to control the mainstream market with the 7700 series, but how does the 7800 series fare amidst AMD’s lead in deploying 28nm GPUs? Let’s find out.

AMD GPU Specification Comparison
  AMD Radeon HD 7870 AMD Radeon HD 7850 AMD Radeon HD 6970 AMD Radeon HD 6950 AMD Radeon HD 5870
Stream Processors 1280 1024 1536 1408 1600
Texture Units 80 64 96 88 80
ROPs 32 32 32 32 32
Core Clock 1000MHz 860MHz 880MHz 800MHz 850MHz
Memory Clock 4.8GHz GDDR5 4.8GHz GDDR5 5.5GHz GDDR5 5.0GHz GDDR5 4.8GHz GDDR5
Memory Bus Width 256-bit 256-bit 256-bit 256-bit 256-bit
Frame Buffer 2GB 2GB 2GB 2GB 1GB
FP64 1/16 1/16 1/4 1/4 1/5
Transistor Count 2.8B 2.8B 2.64B 2.64B 2.15B
PowerTune Limit 190W 150W 250W 200W N/A
Manufacturing Process TSMC 28nm TSMC 28nm TSMC 40nm TSMC 40nm TSMC 40nm
Architecture GCN GCN VLIW4 VLIW4 VLIW5
Price Point $350 $250 N/A N/A N/A

So what exactly is Pitcairn? In a nutshell, take Cape Verde (7700) and double it, and you have Pitcairn. Pitcairn has twice the number of CUs, twice the number of ROPs, twice the memory bandwidth, and of particular importance twice as many geometry engines on the frontend. This works out to 1280 SPs among 20 CUs – organized as a doubling Cape Verde’s interesting 4/3/3 configuration – 80 texture units, 32 ROPs, 512KB L2 cache, and a 256-bit memory bus. Compared to Tahiti, Pitcairn still has 12 fewer CUs and as a result less shader and texturing performance along with the narrower memory bus, but it has the same number of ROPs and the same frontend as its bigger brother, which as we’ll see creates some very interesting situations.

On the functionality side of things, the Cape Verde comparisons continue. As with all Southern Islands family parts, Pitcairn supports things such as DX10+ SSAA, PowerTune, Fast HDMI support, partially resident textures, D3D 11.1 support, and the still-AWOL Video Codec Engine (VCE). FP64 support is once again present, and like Cape Verde it’s a performance-limited implementation for compatibility and software development purposes, with FP64 performance limited to 1/16th FP32 performance.

AMD’s Pitcairn cards will be the Radeon HD 7870 GHz Edition and the Radeon HD 7850. The 7870 is a full Pitcairn, clocked at 1000MHz core and paired with 2GB of GDDR5 running at 4.8GHz. It has a PowerTune limit of 190W while AMD puts its typical board power draw closer to 175, meanwhile idle power consumption is around 10W with a long idle of 3W like the rest of Southern Islands. As for the 7850 it’s the typical lower tier part, featuring 16 active CUs (1024 SPs), an 860MHz core clock, and the same 2GB of GDDR5 running at 4.8GHz as its counterpart, giving it roughly 68% the shading/texturing performance and 86% of the ROP & frontend performance of the 7870. The PowerTune limit is 150W with a typical board power of 130W, and the same 10W/3W idle power consumption as the 7870.

Altogether the 7800 series isn’t just the successor to the Barts based 6800 series in name but also the successor to the 6800 in design. This includes not only power consumption, with one card being a sub-150W part, but also with regards to things such as CrossFire, where it features a single CF connector. Interestingly enough even though Barts was already a fairly small chip for its performance, Pitcairn takes this one step further with a die size of 212mm2, which in turn contains 2.8B transistors, only 160M more than Cayman. As we’ll see when we get to our benchmarks, this makes Pitcairn a surprisingly small chip given its 6970+ performance.

Speaking of the 6970, let’s talk about the 7800 series’ competition. As AMD began winding down Cayman (6900 series) almost immediately with the launch of the 7900 series, at this point the 6900 market has effectively dried up. Having taken themselves out of competition with themselves, AMD’s only competition is NVIDIA’s lineup. From a performance and price basis the 7870 and 7850 don’t map particularly well to any specific NVIDIA products, but generally speaking they’re targeted against the GTX 570 and GTX 560 Ti respectively.

With AMD targeting the ~$320 570 and ~$210 560 Ti and given their conservative pricing on the rest of Southern Islands, it should come as no surprise that the 7800 series is priced equally conservatively. The 7870 will have an MSRP of $350, while the 7850 will have an MSRP of $250. With the 7800 series completing the launch of Southern Islands, this gives AMD a consistent price structure for the entire family: $550, $450, $350, $250, $159, and $109.

Finally, as far as availability goes this will be a delayed launch. AMD is formally unveiling the 7800 series today, but it will not go on sale until the 19th, 2 weeks from now. AMD has said that this is due to both CeBIT and the Game Developers Conference; AMD and their partners want to be able to show off the 7800 series to their respective attendees at those events, with both events being far too large to keep the 7800 under wraps. This delayed launch also means that partner cards aren’t quite ready yet, so we only have AMD’s reference cards on hand. We’ll be taking a look at partner cards later this month.

Spring 2012 GPU Pricing Comparison
Radeon HD 7950 $450 GeForce GTX 580
Radeon HD 7870 $350  
  $330 GeForce GTX 570
Radeon HD 7850 $250  
  $200 GeForce GTX 560 Ti
  $179 GeForce GTX 560
Radeon HD 7770 $159  


Meet The Radeon HD 7870 & Radeon HD 7850


View All Comments

  • ET - Monday, March 05, 2012 - link

    I agree it's kind of disappointing. Even a 5750 was a good improvement over a 3870, and here there's nothing approaching this kind of performance benefit over the 5870 from these. Though I think part of it is that the 5870 still holds up well in many games, as these benchmarks show. Reply
  • Kjella - Monday, March 05, 2012 - link

    I don't think it's that terrible... the 7870 fits pretty much the exact same power envelope as the 5850 and is starting to be a pretty solid performance upgrade. Yes it's a $350 card but inflation adjusted the $279 (pre-hike) 5850 is nearing $300 in 2012 dollars. A good deal and a good cooler (the reference cooler on the 5850 works, but is hardly quiet) and they may get a sale. Just waiting for Ivy Bridge, if nVidia hasn't shown a stunning Kepler by then I think the 7870 is it. Reply
  • Death666Angel - Tuesday, March 06, 2012 - link

    Average increase of 40% in performance and you are comparing a high-end graphics card to a mid-range graphics card. Reply
  • DominionSeraph - Monday, March 05, 2012 - link

    So, AMD discontinued the $250 6950 and $350 6970 to give us... a $250 6950 and $350 6970.

    Not exactly impressed.

    Looks like it will be up to Nvidia to save us, just as they saved us from the price-gouged 5000 series with aggressive release price of the GTX 460 with price drops on the GTX 470. (That one action set the pricing scheme throughout the 6000/500 series)
  • CloudFire - Monday, March 05, 2012 - link

    I'm not upgrading this cycle but I do wish to see Kepler out sooner to drive down prices. This is business and AMD has a few months of no competition so they are going to do all they can to reap massive profits.

    Nvidia isn't going to save you, they would do the same thing if they were in AMD's position. Remember nearly 5 years back with the 8800GTX going for 500+ for over a year? Yea......
  • DominionSeraph - Tuesday, March 06, 2012 - link

    A halo product with no competition is beside the point. We're talking about the 7800 series which sits right in a range where there are competing products, and AMD is pricing it to suck you dry.

    The fact is that the 7000 series is not undercutting the 500 series the way Nvidia undercut the 5000 series. A $250 7850 vs a $270 + free Batman Arkham City GTX 560 Ti 448 Cores is about equal price/performance (maybe a tad in the favor of Nvidia). Contrast this to the GTX 460 being released at $200 when the 5770 was $180. The GTX 460 blew the doors off the 5770 and instantly said the appropriate price for that card is ~$130. A few months later we were seeing $110 5770's and $150 GTX 460's, and that's where we've been at ever since.

    AMD refuses to aggressively compete with Nvidia. They simply slot their products into Nvidia's pricing structure. So prices only change when Nvidia drops theirs and AMD is forced to follow. This means that we, the consumers, are dependent on Nvidia to save us, because AMD sure as hell won't.
  • Exodite - Tuesday, March 06, 2012 - link

    Not really a valid point of comparison though.

    Looking through several reviews of the 7800-series the 7850 lies closer to a 570 than a 560 Ti most of the time, while offering more and better in every possible category.

    Sure, the 7850 isn't on the market yet but assuming the ~250 USD pricing holds true I couldn't possibly recommend a 560 Ti, or even 448 core version, over the 7850 with a straight face.

    It could still be cheaper, sure, but it's nowhere near the pricing disaster the 7900 and 7700 series are.

    To my mind the 7800 series were the ones to wait for.

    Granted, with a 6950 myself I won't be upgrading until the 8k-series at the earliest. Unless Kepler turns out truly amazing, and brings triple display functionality on a single card.
  • tipoo - Monday, March 05, 2012 - link

    If I recall Nvidia hasn't really under-priced AMD in recent memory, they've always tried x more performance sold for >x price. Reply
  • ET - Monday, March 05, 2012 - link

    "AMD discontinued the $250 6950 and $350 6970 to give us... a $250 6950 and $350 6970."

    When you put it this way, it's quite a likeable upgrade actually. Slight boost in performance, lower power and better thermals, upgraded features, all for the same price. What's not to like?
  • chizow - Monday, March 05, 2012 - link

    What's not to like is it took them 16 months to put out a greener refresh sidegrade. Reply

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