Cape Verde GPUs have arrived, Pitcairn will fill in the gap between the high and low end shortly

Today Advanced Micro Devices, Inc. (AMD) continued its rollout of 28 nm Graphics Core Next (GCN) Radeon 7000 series GPUs.  It first introduced the new architecture in Tahiti.  Tahiti enjoyed a soft launch in December 2011, with the Radeon HD 7970 (Tahiti XT), but only began shipping in the second week of January.  At the end of January it dropped a second Tahiti GPU -- the Radeon HD 7950 (Tahiti Pro).

I. Cape Verde -- Finally a Budget-Friendly Radeon 7000 Card

If you thought the $450 and $550 sticker prices for the Radeon HD 7950/7970, respectively, were too high, prepare to be less shell-shocked by the sticker on the Radeon HD 7700 series, AMD's new release, which lands today.

Codenamed Cape Verde, after the 10-island Atlantic Ocean archipelago off the coast off the northwest coast of Africa, the new Radeon HD 7750 and Radeon HD 7770 will land at around $109 USD and $159 USD, respectively.  That sounds pretty good. (But is it really? More later...)

Let's meet the Cape Verde reference card:

Radeon 7750 HD

Radeon 7750 HD

This low price is important for a couple reasons.  First it offers the joys of GCN to budget gamers for the first time.  And second it establishes the competition.  The Radeon HD 7750 is priced almost identically to NVIDIA Corp.'s (NVDA) GeForce 450, while the Radeon HD 7770 falls somewhere between the cheapest GeForce 460s/cheapest GeForce 550s ($140/$130 USD) and the cheapest GeForce 560s ($165 USD).

You might notice here that the bar is set a bit lower for the Radeon HD 7750, due to NVIDIA's lack of offerings on the low budget end, where as the Radeon HD 7770 must essentially tie the GeForce 560 to be taken seriously, thanks to NVIDIA, et al.'s clever pre-emptive rebating. 

As for competition within AMD's lineup, the cards are the direct successor to the Radeon HD 6750/6770 cards, which in turn are rebranded Radeon HD 5750/5770.  

For clarity, we will refer to this previous generation by its rebranded 6000 series name.  But be aware that other articles may be comparing against the Radeon 5750 rather than the Radeon HD 6750 -- but it's the exact same die.

II. The Specs

Whereas the 7900 series easily outmatched its predecessor on paper alone, but was far behind in price, the 7700 series is quite a different story.

On paper Radeon HD 7700 series has less processing units than its direct predecessor, the rebranded Radeon HD 6700 series.  It also can't compete with the predecessor on price.

Clearly the pressure is on for GCN to dramatically outperform its predecessor architecture -- and NVIDIA -- hence warranting keeping the higher price and stripped down core count.

General1 2
Radeon 7700 Basics
(1 "Real world" Power, Noise, and Temperature levels taken courtesy of AnandTech)
(2 All 7000 series GPUs are produced on processes by Taiwan Semiconductor Manufacturing Comp., Ltd. (TPE:2330).)

Core Comparison

In Graphics Core Next's architecture (see below) cores are arranged in blocks called "Compute Units".  Each compute unit packs 64 stream processors and 4 texture units.  Where as the SP counts for the 7900 series made for nice even 4 CU blocks, the 7700 series' lower core counts necessitate AMD to implement one 4 CU block and two 3 CU blocks in the Radeon HD 7770.

Radeon 7770 GCN

Meanwhile the Radeon HD 7750 has two four CU blocks -- the more traditional design.  Each block of CUs shares an L1 instruction and an L1 read-only cache (NVIDIA CUDA users will recognize this as similar to constant memory).  A 512 KB L2 cache pool is shared by all the CU blocks in both designs.


Versus the the 7900 series, which received a nice memory bump, the 7700 series sees a small drop in memory clock.  Otherwise it is identical to its predecessor.
Radeon 7700 Series memory comparison

Specs Wrapup

Uh oh -- things are not looking good for the Radeon HD 7700 series.  Its predecessor has a lower price and more computing units.  But that's just the on-paper comparison.  To the Radeon HD 7700 series credit, it's cooler, more power efficient, in some cases quieter, and offers new features.  But if we don't care about hooking up lots of monitors to our budget card, the card's fate ultimately hangs in GCN.  

III. The Perks

Aside from improved GPU computing with GCN, the cards also pack some other nice perks -- like PowerTune (a major source of the improved power performance), DirectX 11.1 support, Fast HDMI, and the Video Codec Engine (VCE).

A somewhat more complete list is seen below:

Radeon 7700 Features

While all of these features are nice, the question becomes how much they will appeal to budget buyers.  The VCE (smoother video) and Fast HDMI (easier connections to displays) may be appreciated, but PowerTune will likely go unnoticed.  And DX11.1 support is nice, but is likely to go unnoticed and underutilitized given how few games truly exploit it -- and the fact that many of the new tites that do may not perform very well on these cards, due to their bleeding edge graphical demands.

III. Should You Buy This Card?

AMD's Graphics Core Next launch is somewhat analogous to NVIDIA's Fermi.  Like Fermi the chip is quite monolithic, though thanks to die-shrinks it's a little less hot and power hungry.

The biggest justification for this analogy is AMD's new focus on GPU computing with GCN.  This means that for some special instances the Radeon HD 7000 series -- regardless of gaming performance -- will be the card you want to buy.  The HD 6000 series is simply not designed with GPGPU in mind, much as the GeForce 200 Series was far cruder at this task than the GeForce 400 Series.

So the Radeon HD 7700 series wins by default in GPU computing, and certain applications like bitcoin mining (in theory, at least, client support permitting).

But what about gaming?

Anandtech puts it well, stating:

I once had someone comment to me that they can gauge my opinion of a product based solely on the first paragraph of the final page. If I say “there’s no such thing as a bad card, only bad prices” then it’s likely not a favorable review. That statement is once more being validated today, if only in a meta context.


The problem for AMD today isn’t the power/performance curve, it’s the price/performance curve. 16 months ago AMD launched the Radeon HD 6850 at $179 amidst fierce competition from NVIDIA. Ignoring the current price of the 6850 for the moment, on average the 7770 delivers 90% of the 6850’s gaming performance for 90% of the 6850’s launch price. In other words in 16 months AMD has moved nowhere along the price/performance curve – if you go by launch prices you’re getting the same amount of performance per dollar today as you did in October of 2010. In reality the 6850 is much cheaper than that, with a number of cards selling for $159 before a rebate, while several more 6870s sell for $159 after rebate. The 7770 is so far off the price/performance curve that you have to believe that this is either a pricing error or AMD is planning on quickly halting 6800 series production.

Now things aren't quite as dire as that statement might have you believe.  Returning to the GCN/gaming question, GCN does actually deliver, as the above statement indicates.  The Radeon HD 7750 almost holds its own with the $10 USD more expensive GeForce 550 Ti and beats its higher-core predecessor.

Likewise the Radeon HD 7770 beats its predecessor, nears the performance of the Radeon HD 6850, and manages to avoid getting totally blown out of the water by the GeForce 560.

Ultimately the Radeon HD 7750 seems more appealing than the Radeon HD 7770 -- but largely due to lack of competition on the very low end.  Is the Radeon HD 7750 the card to buy?  If you are buying a budget card now, particularly if you're going to do GPU computing, this is a decent pick, absolutely.  Yes -- it is a decent buy.

By contrast, the Radeon HD 7770 is not.  The GeForce 560 is selling for $165 USD with rebate.  It's a better GPU computing card, and it performs substantially better in games -- much more than $5 USD better, based on Anandtech's tests.

Where as price on the 7900 series was a headache, it at least was justified in performance.  But the performance of the Radeon HD 7770 cannot justify its $160 USD sticker, when the GeForce 560 is $165 USD.  All the cool features in the world have a very tough time changing that cold hard reality, particularly to a budget buyer.

AMD, et al. needs a price cut for the Radeon HD 7770.  No ifs, ands, or buts.

The concerning reality is that the price may be less a reflection of AMD's desired price point, but more a reflection of yield difficulties at 28 nm.  TSMC was reportedly having a lot of issues with yields as recently as a couple months ago, according to several trusted sources.  This could be driving up prices.  And it may be why we've seen a delay in NVIDIA's 600/700 (Kepler) series announcement.

We tried to inquire about this, but were given a non-answer, "[Yields] is a question for TSMC. But Cape Verde is a volume part."

Okay, let's just assume there are yield difficulties.  This could play out one of two ways -- one the early relationship with TSMC at the 28 nm node may allow AMD to gain greater production access than NVIDIA later on and suffer less difficulties.  In that regard, the pain we're seeing may pay off.  On the other hand, if NVIDIA jumps in and is able to get all the volume it wants from TSMC and better yields, AMD's early adoption of the die shrink may backfire.  Only time will tell which is true.

But time is immaterial to the press price weaknesses of this launch.

IV. What's Next? (Outlook/"Big Picture")

So you know a bit of the good and bad with the 7700 series.  The final fact you need to know is that this is a hard launch, so product will begin shipping today.  AMD gives a nice list of its partners, below:

Radeon partners

Cape Verde is the second of three major releases on the desktop side for the 7000 series (Southern Islands) family of GPUs.  The final major Southern Islands release will be Pitcairn (Radeon 7800 HD series), which is expected to land in March.

Radeon 7700 Series

Be aware, AMD is already (as of January) shipping other Southern Islands ultra-budget parts to OEMs (Radeon HD 7500/7600 Turks series; Radeon HD 7400 Caicos? series; and Radeon HD 7300 Cedar? series).  AMD has announced no plans to sell these as discrete GPUs, but it is possible it may begin to do so, assuming yields at TSMC go well.

The logical next step would be to release mobile variants.  Expect this to happen sometime around Q3, giving the likely yield troubles.  

AMD is being rather cagey about the prospect of mobile offerings, for now, stating, "I'm afraid we can't comment on that yet."

In a way mobile GPUs may be less of a concern for AMD, with it pushing hard to incorporate elements of Graphics Core Next into the new Trinity APUs and their next-generation 2013 successor, Kaveri.  However, beefier mobile GPUs are important for the same reason that pricey discrete GPUs are still relevant -- gamers and artists want them.  On-die APU graphics cores just aren't going to cut it for all users.  So AMD certainly should deliver something in this segment later this year.

AMD needs a hit with the 7000 series, because the 6000 series disappointed, in terms of sales.  Even AMD's own slide (which compares exclusively DirectX 11 capable GPUs) hints at this:

Radeon 5000 Sales Performance

Looking at the current numbers, it appears that there's about 4 times as many Radeon HD 5770s in the wild as there are the top 6000 series card, the Radeon HD 6950.

AMD clearly needs another 5000 series like performance, not another 6000 series.  But unfortunately, the inflated pricing of the 7700 series is a major barrier to replicating that success.  AMD is fortunate in that it has some time to bide before Kepler drops.  But even versus NVIDIA's aging 500 series, the 7000 series pricing ranges from disappointing to plain unacceptable (as in the case of the Radeon HD 7770).

It should be interesting how the tech public reacts.

Sources: AMD, Anandtech [power, noise, temp. results]

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