Nehalem Xeons: The Future Of Core i5?
An Approach Of Opposites
Intel and AMD have traditionally taken opposite approaches to introducing new CPU architectures. AMD always debuts a new architecture as a part for server and enterprise applications first. In the latest round it debuted the Phenom II consumer parts first as the Shanghai-series Opterons. Intel, on the other hand, has always done the reverse. Intel product launches tend to focus first on high-end consumer components, followed then by server parts. Last year consumers got a hold of Core i7, but it is only as of this month (April) that Intel has started to send out Xeon processors.
Often times, these server releases represent half-steps from the consumer perspective (and those interested in servers probably see consumer products as being half-steps between new server product lines). This does not seem to be applicable in the case of the Nehalem Xeon products, however, although this is likely the case because Intel, despite debuting the consumer-level products first, seems to have been focusing heavily on performance in high-end workstation, server, and enterprise applications when designing the Nehalem architecture. Everything about Nehalem is obviously geared towards business applications which require massive amounts of computing power capable of taking advantage of numerous threads.
Learning From Xeon
The Xeon product lineup provides a glimpse into what future consumer Nehalem chips will look like. At the high end, we see the expected products, consisting of four-core processors with high clock speeds, 8MB of cache, high maximum DDR3 speeds, and hyper-threading support. In these cases the Nehalem Xeons are basically identical to the Core i7 processors currently available to the market.
More enlightening is the lower-end server products, such as the Xeon E5502 with a clock speed of 1.86Ghz, two cores, and hyper-threading disabled. This part is likely to be re-incarnated as some form of Nehalem processor on a 32nm manufacturing process. The same likely holds true for Xeons like the E5520, a 2.26Ghz Quad-Core. I think that taking a look at the performance of these processors would provide some serious insights into how mainstream Core i5 processors will perform once they begin to hit markets later this year. Unfortunately these low-end parts have gathered no interest from reviewers. Still, we can see that the E5502 is a four-core processor with two cores disabled, and that it has a TDP of 80W, which seems a bit high. I think we will see dual-core Nehalem products which are quad-core products with two cores disabled around the end of this year or early into 2010, and the specs will be similar to what is seen on the E5502.
Also interesting are the “L” series Xeon products, the L5520 and L5506, clocked at 2.26Ghz and 2.13Ghz respectively. These parts are interesting because they are 60W parts, which is quite low for a quad-core part even at these clock speeds. Considering that Intel has already debuted power-saving versions of its Core 2 Quads, I believe this is indicative that Intel is going to carry through with a line-up of “green” parts that will eventually span through Core i5, Xeon, Core 2 Quad, and possibly Core i7. Although I personally am not excited by this, a 60W quad-core should appeal to those who need to keep capable hardware in small spaces with poor airflow. It will also give PC makers ammo for advertising eco-friendly versions of its computers.
Core i5 and Core i7 - Separated By Sockets
Something that is becoming abundantly clear is that Core i5 and Core i7 are meant to be separated by sockets to create very specific platforms for two separate areas of the market. This is likely because Intel has traditionally had a difficult time justifying the existence of its high-end X-series desktop chipsets. The X48 chipset was wonderful, but it was not significantly better than the P45 or even P43 in numerous ways, including overclocking potential and real-world usability for most consumers. Motherboard sales figures do not really exist, but the trend among enthusiasts is to place very high-end processors is fairly cheap motherboards, as it presents the better value. Gamers often skimp on the CPU in favour of better graphics or a motherboard that can support said graphics. Intel likely wants to stop this pick and choose, and I think this is a partial motivation for the creation of the LGA1156 for Core i5 and the LGA1366 for Core i7.
The large disparity in the needs of high-end users and average users is also a likely motivation for this separation. Because many users continue to use their computers only for basic tasks like word-processing and web-surfing, it is becoming difficult to see why Intel should aim to push hard on the performance of desktop computers. It seems more sensible to begin to lump the needs of enthusiasts with those of enterprise customers, as the disparity between a workstation and a super tricked home PC is arguably smaller than the gap between low and high-end PCs. It also allows Intel to force people who want fully featured motherboards, like those with 32 lanes of SLI or Crossfire support, to step up to Core i7, described here.
That said, it is not at this time obvious how Core i5 will be inferior to Core i7. Sure, the non-processor advantages, like triple chanel memory, are on Core i7’s side, but Intel’s reported specs fore Core i5 processors seem to indicate that they should perform even better than current Core i7 products. This likely means that the amount of room available to the Core i7 brand will be slim, as only the most powerful components will be able to fit into that line-up. It is also likely that the debut Core i5 processors will remain the highest performing Core i5 processors that will be seen for some time, as going higher would cannibalize less powerful Core i7 parts. Another possible reason as to why Intel is making the first Core i5 processors so powerful is the need to sell off excess stock of Core 2 products before selling low-end Core i5 parts.This could force Intel to delay the six core Gulftown chip planned for Core i7 early next year. In either case, the distinction between Core i5 and i7 should become apparent as Nehalem matures and Intel begins to introduce low-end Core i5 parts.
In either case, the distinction between Core i5 and i7 should become apparent as Nehalem matures and Intel begins to introduce ultra-low-end Core i5 parts. It is likely at this point that parts with two cores disabled will actually be marketed under a Core i3 name, using socket LGA1155. This starts to run into the realm of serious speculation, however, as there are conflicting reports which include a huge range of rumored sockets, including a mobile mPGA-989, a server LGA1567, and others.
A Varying Plan
As with all articles about future plans for a processor company, this is largely speculation. This speculation is generally rather accurate simply because Intel is a predictable company. They’ve never been very shy about showing off new architectures before they arrive on the market, and Intel roadmaps are usually spot-on.
That said, the current global recession does throw a wrench into the normally smooth mechanics of the corporation. Earlier this year Intel replaced the Havendales which were supposed to be 45nm chips with two cores and integrated graphics arriving sometime midway through 2009, with Clarkdales to be introduced at year end instead as a 32nm, Westmere, part with on chip graphics. Intel got rid of the 45nm plan because of the approach of the move to 32nm and because of the slump in desktop computer sales. The current recession comes at a particularly poor time for Intel, as the company’s transition to Nehalem processors means that it needs to sell off extra stock of Core 2 based processors. Slumping consumer spending makes this harder for Intel to do, and could delay Intel’s plans in a variety of ways. The Calpella laptop platform, which will bring Nehalem to mobile computers, has been delayed to help OEMs move Core 2 inventory, and examples of these economically driven delays may continue to occur depending on sales of Core 2 products.
This post is part of the series: Intel Core i5 and i7 Performance Review
How do Intel’s Core i5 and i7 processors stand up in performance? These articles explore their performance in gaming, productivity, and workstation applications.
