When the Intel Developer Forum kicks off Tuesday in San Francisco, the theme of low power will be high on the agenda of topics.

The headliner at IDF this year is indisputably the upcoming "Nehalem" Core i7 processor. Though the new microarchitecture is replete with esoteric technologies like QuickPath (for faster chip-to-chip communication) and on-chip memory controllers--things that end users can't readily relate to--better power efficiency is something every consumer gets because it results in better battery life.
"(Nehalem) is pretty subtle because it's a change in microarchitecture. A lot of the changes aren't all that visible to the end user. But one of the most notable (changes) is power saving," said Roger Kay, founder and president of Endpoint Technologies.
This won't become apparent to many consumers, however, until Nehalem mobile processors hit the market, according to Kay. "Nehalem notebooks should have dramatically longer batter life," Kay said. Nehalem mobile chips will not appear until next year.
Overall, Nehalem is better than previous Intel architectures at scaling up performance while keeping a lid on power consumption. So, for example, a Nehalem quad-core desktop processor may deliver better performance at power levels equal to current Core 2 quad processors--so Intel says. Nehalem will have all four cores on one piece of silicon, a first for Intel in the mainstream market.
An Intel IDF blurb that describes the technological highlights of Nehalem also states that chips will have "dramatic new energy efficiency gains when workloads are scaled back." Intel will presumably clarify nebulous statements like this at IDF.
In the more immediate future, Maximum PC recently tested a Nehalem "Bloomfield" desktop system that uses a 2.93GHz processor and an Intel motherboard with an X58 chipset. Both of these are expected to ship in the fourth quarter.
Atom is next on the short list of high-profile topics--and Atom is all about power efficiency, not high performance. The tiny mobile chip has a power envelope not exceeding 2.5 watts, far below the 35-watt power envelope of mainstream Intel mobile processors to date.
Though Anand Chandrasekher, general manager of Intel's Ultra Mobility Group, will talk about Atom in handheld mobile Internet devices and discuss Moorestown, the next iteration of Atom, the netbook category is the driving force behind Atom right now. David (Dadi) Perlmutter, general manager of Intel's Mobility Group, will talk about the low-cost mobile market and show off a variety of netbooks, according to Intel.
Current high-profile netbooks include the Asus Eee PC and Acer Aspire.
Since netbooks are synonymous with low power don't expect dual-core Atom processors from Intel designed specifically for netbooks anytime soon, according to Bill Calder, an Intel spokesperson. "There's no reason to do dual core in the netbook. Single-core Atom is perfectly adequate," Calder said. (Dual-core Atom chips for "nettop" desktops are coming by the end of the year.)
"These things are intended for basic Internet use. Mostly reading, sharing, viewing. Not creating, building, burning," Calder said.
Intel will also mention more about it's ultra-low-voltage (ULV) mobile processors. These are essentially Core 2 mobile processors designed for the stringent power requirements of ultralight notebooks like the MacBook Air, Lenovo X300, and the just-introduced Dell 12-inch Latitude E4200.
The current ultra-low-voltage lineup will be refreshed in September with 45-nanometer parts. All LV and ULV processors being sold now are based on older 65-nanometer technology.
Dual-core processors in this category have thermal envelopes as low as 10 watts, though more mainstream low-power processors (like those in the MacBook Air) will fall somewhere between 10 and 25 watts.
Many of these sub-one-inch-thick notebooks will also offer 80GB and 128GB solid state drive options. Micron Technology has introduced solid state drives in 128GB and 256GB sizes. Large-capacity SSDs will be part and parcel of ultralight notebook offerings in the coming months.
At the high end of power spectrum, Intel will also talk more about its first quad-core mobile processor. Both Hewlett-Packard and Lenovo are already showing off quad-core laptops and HP lists the quad-core mobile chip as an option on its EliteBook 8730w mobile workstation. The quad-core mobile processor is also expected to appear in gaming laptops from Dell's Alienware unit.