Intel makes a lot of processors. Too many, maybe. Don't know the difference between a Core i7 and a Core 2 Duo? A Bloomfield from a Wolfdale? A Sasquatch from a Yeti? You're not alone.
Chips, Chipsets and Damned Chipsets
OK, so the first thing to understand is that an Intel brand, like Core 2 or Core i7, actually refers to a whole bunch of different processors. Although they generally have the same basic microarchitecture (in other words, chip design), the brand envelopes both desktop and mobile chips, chips with radically different clock speeds, that use different motherboard sockets, etc.
Because of these differences, each particular chip is given a codename, chosen for obscure geographical locations (seriously, plug just about any codename into Google Maps). For instance, the original mobile Core 2 Duo processor was Merom, and it was replaced after about two years by Penryn, which was manufactured using a new 45-nanometre process to be more efficient. Quite different, these two, but Intel pimped both as Core 2 Duos nonetheless.
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Although Intel doesn't market chips according to their codenames, the individual chip gets a model number that gives you an idea of how it compares, spec-wise (clock speed, cache size, etc.), to other chips in the same group. So, a Core i7-950 is gonna be faster than a Core i7-920, and a Core 2 Duo P8600 isn't going to quite stack up to a Core 2 Duo P9600. The difference between a P8400 and P8600 is obviously less than the difference between a P8600 and a P9600. To match a particular chip codename to a particular model number though, you probably have to do some Googlin' (or Bingin').
In some cases, Intel pushes chips with a ULV designator for "ultra-low voltage", which doesn't mean anything in particular in terms of chip design, since it includes several brands of chips, from Core 2 to Celeron. The point is that these chips power notebooks that are almost as portable at netbooks, but are more expensive, so computer makers (and Intel) make more money.
While we're at it, I might as well explain what the hell Centrino is. It's not a single chip, it's a platform. That is, it's a combo meal for notebooks with a mobile processor, a chipset (essentially the silicon that lets the processor talk to the rest of the computer) and a wireless networking adaptor. Typically, Intel releases a new combo meal every year, though they've all been called Centrino, with the most recent making the leap to being called Centrino 2.
The reason we decided to tell you all this stuff now is that Intel is gradually phasing out the Core 2 family, like Pentiums before that, and is moving Core i7, Core i5 and Core i3 up to take its place. This is how all the families relate to each other...
Nehalem Rising: Core i7, Core i5 and Core i3
Core i7 systems use a totally new microarchitecture called Nehalem, and it's badass.
The first set of Core i7 chips, codenamed Bloomfield, launched in November 2008 for high-end desktops. They're the most outrageously fast Core i7 chips, with triple-channel memory (meaning they're able to use memory sticks in triplets rather than pairs) and other blazing accoutrements.
The new Core i7 chips, launched last month, are for desktop and mobile. The desktop variant is codenamed Lynnfield, and it more closely resembles its mobile equivalent, codenamed Clarksfield, than it does the Bloomfield monster — dual-channel memory, not triple, for instance.
You'll be seeing a lot more Clarksfield in the next couple weeks, like in the HP Envy 15, since most computer makers were holding off for Windows 7 to drop their new laptops. All of the Core i7 processors are quad-core, even the mobile Clarksfield, so you're not gonna see it in anything like Dell's skinny Adamo.
Core i5 is going to be Intel's more mainstream Nehalem-microarchitecture chip brand, and as a broader brand, the chip differentiation gets a little more confusing. Core i5 actually includes some (but not all) of the desktop Lynnfield processors. For now, the only Core i5 chip is quad-core, but you're going to start seeing dual-core Core i5 chips, and soon enough they will make up the bulk of Intel's mainstream processors. In English: Unless you're looking for a crazyfast new computer, your next machine will probably run an Intel Core i5 CPU.
Eventually, dual-core Core i3 chips will come out, and as you can guess by the number, they won't be quite as fast—or expensive—as the Core i5 or i7 chips.
Netbook's Best Friend: Atom N and Z
Atom is probably the Intel chip you hear about second only to Core 2 Duo: It's essentially the CPU that goes inside of netbooks. There are a couple of different variations out now, the N series (codename Diamondville) and the Z series (codename Silverthorne). The Diamondville chips are for nettops and netbooks, and can handle full versions of Windows Vista and 7. Silverthrone is used in netbooks but was designed for smaller connected devices like UMPCs and MIDs. (This is why Sony shoving an underpowered Atom Z in the Vaio P, and trying to run Windows Vista on top of it, was retarded.)
The next generation of Atom is more interesting, and more confusing, in a way. The CPU is codenamed Pineview, and it's actually got the graphics processor integrated right onto the same chip, precluding the need for a separate GPU tucked into the netbook's overall chipset. The benefit is longer battery life, since it'll take less energy to crunch the same visuals. We'll start seeing Pineview netbooks sometime early next year, most likely.
Oldies But Goodies: Core 2 Duo, Quad and Extreme
Intel's Core 2 chips have been out three years now, an eternity in computer years. Because of this, and because they're the main ones used in most personal desktop and laptop systems, there is a metric shitton of different Core 2 chips.
It's also more confusing because there are way more codenames to wade through. Let's start from the top: Core 2 Solo has one core, Core 2 Duo two, and Quad has four (as does Extreme). From there, you have two distinct generations of chips within the Core 2 family.
In the first generation of Core 2 Duos, the main desktop chip was Conroe (with a cheaper variant called Allendale), while the main mobile one was called Merom. There was also a branch of Core 2 Quads called Kentsfield.
The next generation (that is, the current generation, unless you're already on the Core i7 bandwagon) arrived with a new process for making chips with even smaller transistors. Among other more technical differences, they were more energy efficient than their predecessors. With this generation of Core 2s, the mainstream desktop chips are Wolfdale, the desktop quad-cores are called Yorkfield, and the mobile chips are Penryn — if you've bought a decent notebook in the last two years, it's probably got a Penryn Core 2 inside of it.
Ancient History: Pentium and Celeron Pentium is dead, except it's not, living on as a zombie brand for chips that aren't as good as Core chips, but aren't as crappy as Intel's low-end Celeron processors. If you see a machine with a sticker for Pentium or Celeron, run.
OK, I hope that helps, at least a little — you should probably thank me for staying away from clock speeds and other small variations, like individual permutations of Core i7 Bloomfield processors, to hopefully give you a broader overview of what all's going on. Intel told me it'll all make more sense once their entire road map for the year is out on the market, but I have a feeling it's not gonna help my mum understand this crap one bit better.
Top image via soleiletoile/Flickr
Thanks to Intel for helping us sort all this out!