We should pause briefly to let you know that Intel may attempt to confuse you by referring to Sandy Bridge-based products as "second-generation Core microprocessors." Do not be taken in by this strange attempt at marketing. What they are talking about is not the Merom/Conroe generation of chips, sold under the "Core 2" banner and based on the microarchitecture known as Core. Nor are they talking about Nehalem chips based on the second-generation Core microarchitecture and sold as Core i3, i5, and i7. No, that would be entirely too simple. They're also not talking about the later Westmere/Gulftown chips, which comprised the second generation of processors to fall under the Core i3/i5/i7 naming scheme. Nope! What Intel means when it uses this funny turn of phrase is, strangely enough, Sandy Bridge-based processors. How they are the second generation of anything with a Core name on it is beyond me, but you may want to file away this information unless the phrase comes up. There's probably no good way to map it out logically, so memorization may be key.
While I'm complaining about confusing marketing, let's have a look at the Sandy Bridge product stack. Normally, we'd make up a nifty, blue table with all of the various models and their key specifications, but this time, I've decided to relay it to you just as it came to us from Intel. Apologies for the small lettering, but there's a lot to cram into the space.
Listed above are just the desktop variants of Sandy Bridge being announced today, and only those within the traditional lineup. There are also low-power S models and even lower-power LV variants intended for small-form-factor PCs, along with "supplemental" models aimed only at large PC manufacturers—not to mention the mobile versions for laptops and such, which are increasingly important. In all, Intel is announcing 29 new CPU models and 10 different chipset variants today.
The sheer variety itself isn't a huge problem, but you'll want to watch carefully before buying a Core ix-2000-series processor because, given a great number of possible knobs and dials it could tune in order to differentiate its various CPU models, Intel has chosen to twiddle with virtually all of them—base and Turbo clock speeds, core count, thread count, L3 cache size, IGP type, you name it. If there's a feature you want or need, there's no guarantee that just buying a new processor get it for you. (The difference between the HD 2000 and 3000 IGPs, incidentally, is the number of execution units; the 2000 has only six enabled, while the 3000 has 12.) Intel has no doubt been wildly successful over the years and will likely continue to be with these new products. Still, we can't help but wonder whether that success has come in spite of its product segmentation practices, which are surely incredibly confusing to most consumers, rather than because of them.
With that complaint out of the way, the wonderful thing you'll want to notice about Sandy Bridge is that she's really quite an affordable date. The most expensive, unlocked K-series quad-core, the i7-2600K, rings up at only $317. The rest of the lineup costs less and extends down to the $117 Core-i3 2100, a 3.1GHz dual-core. These really are mid-range and lower parts. Intel is leaving the high end to its venerable LGA1366 socket and Gulftown-based six-core processors. Whether the Sandy Bridge quads will challenge the Gulftown parts on performance, though, is quite another story, as we'll soon see.
The quad-core versions of Sandy Bridge listed above should be available for purchase as soon as you read this text. The dual-cores, in both desktop and mobile form, are slated to reach the market in four to five weeks.
New socket, new chipsets
The vast changes to Intel's CPU silicon bring with them big changes to the surrounding infrastructure, including a new socket type and new chipsets. You can't plug a Sandy Bridge processor into an older LGA1156-type motherboard, and trying might leave you with a mangled socket, since the new LGA1155 socket is a different animal with the retention notches in another location. Believe me, I came close to closing the lid on a socket with the wrong chip type inadvertently in place, which would have been catastrophic. Look closely at the pictures below, and you'll see the difference.
In short, you're going to need a new motherboard in order to build a system around a Sandy Bridge CPU. Although Intel has a host of different chipsets targeted at different markets, that mobo will likely be based on one of two offerings: the performance-oriented P67 or the more pedestrian H67.
These new chipsets have a handful of nice improvements over the prior-gen P55 and friends, including the fact that the eight PCI Express lanes branching off of the chipset now transfer data at 5 Gbps, the full rate supported by PCIe 2.0, rather than half that. The increase should help for auxiliary I/O chips like USB 3.0 and SATA 6Gbps controllers. Speaking of which, the chipset itself now has a pair of SATA 6Gbps ports built right in, along with four more SATA 3Gbps ports. The only really glaring omission here is USB 3.0 support, which most motherboard makers have overcome by using third-party USB controllers.
One thing that you'll want to watch for in Sandy Bridge mobos: with the new Turbo algorithm, our understanding is that VRM design can potentially influence the amount of time the processor spends resident in Turbo mode clock speeds. It's possible motherboard designs may once again influence overall performance in way that they haven't for several years. Could make things interesting. Stay tuned for Geoff's take on four of the first such boards based on the P67, which we should be posting soon.