Barcelona: AMD Gambles on an Evolutionary, Not Revolutionary, CPU

It will be the first commercially available x86 processor to provide four cores on a single die - to manage four logic units with a single, internal controller. By all rights, AMD's quad-core Opteron, officially announced today for availability this month, should be a milestone in CPU architecture. But Intel has had plenty of time - in fact, several months more than the market had originally anticipated - to implement performance tweaks and power gains that could perhaps compensate for the significant boosts that customers are expecting from quad-core Opteron.

AMD's gamble is that everything Intel has done to this point to make up ground won't be enough. "To us, it's more important to bring new functionality and new levels of performance in the same platform, than it is to rev the platform every six months," said John Fruehe, AMD's worldwide market development manager, in an interview with BetaNews.

The story of quad-core Opteron is that of a company asking its customer base to keep the faith, even in the midst of several extremely tempting revisions from Intel over the course of the last 14 months. AMD implemented design decisions as far back as the first quarter of 2002 that it hoped would lead the company, in carefully staged increments, through the first few stages of the multicore era.

Quad-core Opteron is not a revolutionary processor. Though it may indeed be the first "true quad-core," with all four logic units embedded in one die with an on-chip memory controller, the "Barcelona" architecture is really just another step in a long chain.

Barcelona Issue #1: How stable is the platform?

While Intel has clearly worked to upstage this morning's Barcelona unveiling, most recently just last Wednesday with the introduction of its own quad-core "Tigerton" line, many of Intel's latest innovations - Tigerton among them - rely on new chipsets. Though the Woodcrest CPU was dedicated to the 5000 series chipset, when the two-way Clovertown edition was released four months later, it preferred the 5300 series.

For multi-processor Intel setups, it's been a similar story. Paxville represented Intel's first dual-core foray into the server field in 2005. It used the E8500 chipset. When the Tulsa CPU with the 16 MB L3 cache support was released nine months later, it was said to be "happier" with the E8501. And the chorus was repeated again last week, as the more power-sensitive, double-dual-core Tigerton revolves around Intel's Clarksboro 7300 series chipset.

So AMD's message today is designed to appeal to the system builder or OEM that doesn't want to find itself dependent upon Intel's self-dubbed "cadence," which involves migrating between platform generations and not just CPUs. AMD's John Fruehe (pronounced "free") told us his customers don't call it a "cadence."

"IT directors call it a living nightmare," he said.

"Our OEM customers appreciate a nice, long lifecycle so that they do a bunch of work at the beginning, and as each new processor comes out, it's a little bit of validation that they have to do to have that ready." By contrast, he added, Intel Xeon MP customers, "in the course of really 18 months, are going through four or five platform iterations. That really takes its toll on both the OEM customers and then, from an end-user customer standpoint, you're looking at multiple platforms that you've got to support within your data center. And that just becomes a whole lot of work.

"The nice thing about Barcelona is, it literally drops into the existing platforms. So if you've got existing dual-core servers, it should be easily upgradeable to Barcelona."

Rather than invest in an entirely new platform, AMD is asking its Barcelona customers just to purchase the chip, and drop it into their existing dual-core Opteron systems. The new chip continues to use Socket F, the 1207-pin connector introduced in August of last year. The power requirements and the thermal envelope will be the same, so Quad-Core Opteron will draw little or no more power than Socket F Dual-Core Opteron, including the two-way 2200 series and the eight-way 8800 series.

"So if you're an OEM and you designed a platform around it, or you're a system builder and you've customized the platform for your customers," Fruehe told us, "there's not a whole lot of work that you have to do to be able to support Barcelona. And, most importantly if you're a customer, you get to have the same software image, whether it's dual-core or quad-core. So that cuts down a lot of the overhead of managing large data centers, where you've got dozens of different platforms that span multiple years.

"If [the customer] says, 'This platform looks exactly like my other platform, there's nothing new and there's no big news to that,' that's the point where every CIO stands up and gives us a standing ovation," he continued. "We're able to deliver that significant performance increase and yet power and thermals stay the same, so that they don't have to change data center designs; the platform stays the same, they don't have to change out system boards; and that's where they start to get really excited."

Next: Barcelona Issue #2: Were All AMD's Design Choices 'Smarter?'