I can't help but wonder what's gone through the heads of the engineers who designed Intel's Atom CPU. Envisioned as an x86-compatible computing platform that could eventually make its way into smart phones, the first iteration of the Atom was targeted at Mobile Internet Devices (MIDs)glorified web tablets with basic multimedia playback capabilities. MIDs never really caught on, though. That's just as well, because the Atom had another destiny: fueling a revolution in the notebook world courtesy of a new class of budget ultraportables that came to be known as netbooks.
Yes, the seminal Eee PC ran an underclocked Celeron rather than an Atom CPU. But netbooks really didn't catch on until the Atom and its associated Diamondville platform became available. The original Atom N270 had just enough horsepower to handle basic web surfing, email, office document manipulation, and standard-definition video playback. Plus, it was power-efficient enough to deliver more than five hours of real-world battery life in ultraportables that tipped the scales at under three pounds and cost around $400. No wonder everyone from mobo makers like Asus, Gigabyte, and MSI, to system giants like Acer, Dell, and HP, were eager to get into the netbook game.
Before netbooks came along, new ultraportables didn't often dip below the $1,000 mark. Most were premium models that cost well over a grand. The Atom opened this previously exclusive market to the masses, and the rest is history. According to an ABI Research report quoted by Intel, about 50 million netbooks will have sold by the end of this year. Another 60 million are predicted to reach consumers in 2010.
The Atom didn't stop at netbooks, either. It also spilled into the desktop world, where the CPU can be found driving low-cost nettops, mini home-theater PCs, all-in-one systems strapped to the back of LCD monitors, network-attached storage rigs with multi-drive RAID arrays, and even Mini-ITX motherboards.
One of the most surprising things about the Atom's rise is the fact that this all-new CPU has managed to succeed while tied to an antiquated chipset whose roots can be traced all the way back to 2005. Atom processors are usually accompanied by two additional bits of silicon: a 945GSE north bridge chip with GMA 950 integrated graphics and an ICH7M south bridge chip. Not only do these older core-logic components lack the sort of features one might expect from a modern chipset with integrated graphics, but they also draw quite a lot of power. The 945GSE/ICH7M combo has a TDP rating of 9.3Wnearly four times the 2.5W TDP of the Atom N270 CPU found in most netbooks. The chipset has a rather large footprint, too; its north and south bridge components have a combined package area of 1,690 mm², which works out to about 3.5 times the size of the Atom's 484 mm² Micro-FBGA package. Millimeters might not seem like much, but they count for a lot when you're working within the constrained proportions of typical netbook designs.
More than a year has passed since the first Atom platform debuted, and Intel is finally ready to release its much-anticipated successor. Code-named Pine Trail, this second-generation platform's most interesting element is again the CPUotherwise known as Pineview. The intrigue has little to do with changes to the actual processor core, though.
Intel declined to comment on any specific modifications to the new Atom's CPU core, instead pointing us to data sheets that suggest that little has changed. This latest Atom retains the in-order architecture of its forebear, complete with Hyper-Threading support. The cache structure also appears to be unchanged, with 56KB of L1 split between 32KB instruction and 24KB data caches and 512KB of L2 cache associated with each physical core.
Even clock speeds haven't budged. Intel is announcing the Atom N450, D410, and D510 models today, and they all run at 1.66GHz, just like the old N280. The N450 and D410 feature a single core that can execute two threads in parallel, while the D510 has two cores and can handle four concurrent threads. All three chips are manufactured using a high-k, 45-nm fabrication process, but their TDPs vary somewhat. The netbook-oriented N450 has a 5.5W TDP, while the desktop-bound D410 and D510 have TDP ratings of 10W and 13W, respectively.
But wait, the original Atom had a 2.5W TDP. Where's all the extra power going? To the rest of the chip, which now integrates a memory controller and a graphics processor on the same die as the CPU. The memory controller is a single-channel affair, and somewhat surprisingly, it supports old-school DDR2 rather than DDR3 memory. N-series Atom CPUs destined for netbooks can use up to 2GB of DDR2-667, while D-series desktop chips are capable of handling as much as 4GB of memory at up to an effective 800MHz.
Memory bandwidth will be in high demand because system memory is shared with the Atom's integrated Graphics Media Accelerator 3150. This graphics core is based on the GMA X3100 found in Intel's G31 Express desktop chipsets. That's technically an upgrade over Diamondville's GMA 950, but don't get your hopes up. The GMA 3150 may support DirectX 9 and Shader Model 2.0, but it's limited to two pixel pipelines and a core clock speed of only 200MHz in netbooks. D-series Atoms get a graphics clock boost to 400MHz, which still isn't going to be enough for 3D gaming. More troubling, however, is the lack of HD video decode acceleration. The GMA 3150 can assist the decoding of plain old MPEG2 video, but that's about it. Intel recommends using an auxiliary video decoder chip, available from third parties like Broadcom, to facilitate HD video playback.
Pineview has its own display outputs, although they're quite limited. Literally. An LVDS output that tops out at 1366x768 is the sole digital display pipe. The VGA output is capped, too, at 1400x1050 for the N series and 2048x1536 for the D series, respectively. Home-theater PC implementations are going to need a helping hand in order to drive 1080p display over HDMI.
The only assistance Intel gives Pineview is a "Tiger Point" chipset: the NM10 Express, although it's not really a set of chips at all. In Intel's parlance, the NM10 is platform controller hub, or PCH, much like the single external P55 chip used in Lynnfield desktop systems. This mini PCH serves up a couple of Serial ATA ports, eight USB 2.0 ports, a 10/100 Fast Ethernet MAC, and an HD audio interface. There's also room to grow via four first-generation PCI Express lanes that can be divided evenly between four x1 links or consolidated into a single x4 connection for, perhaps, a potent discrete graphics processor. Ion 2, anyone?
Intel links its new Atom CPUs to the NM10 Express via a PCIe-like DMI link that offers 1GB/s of bandwidth on N-Series Atoms and twice that with desktop chips. Each DMI lane boasts 250MB/s of bi-directional bandwidth, just like gen-one PCI Express. Desktops get four lanes and netbooks must make do with two.
Overall, Pine Trail isn't so much about new features as it is an exercise in consolidation. Where once there were three chips, now only two remain. The Atom platform's physical footprint has shrunk by a factor of three, down from 2,174 mm² to 773 mm². Total platform power is lower, too. Netbook implementations of Pine Trail have a combined TDP of just 7W (5.5W for the CPU and 1.5W for the chipset), which is 40% lower than Diamondville's TDP. For desktop variants, you're looking at a TDP of 12 or 15W, depending on the D-series processor used. The NM10 Express has a 2W TDP when used in desktops and a 1.5W TDP rating for netbooks.