Mobile CPU Roadmap: Picking the Right Intel Chip

Dec 30, 2011

Intel’s Core family of chips has the right stuff for laptop users, from the Core i3 all the way up to the deluxe Core i7. Choosing the right laptop means knowing your mobile CPUs. We’ll explore the key features of Intel’s mobile chips to help you find the best one for your needs.

Published: September 16, 2010

Processor speed has peaked in recent years, but core counts, power-saving features, and built-in functionality have continued to climb. And with the industry emphasizing power consumption and performance per watt, mobile CPUs are where much of the most significant innovation is happening these days. As these CPUs have proliferated, deciding which one is right for you can be confusing.
Case in point: Intel’s Core family of processors, with an alphabet soup of names like i3-350M, i3-330UM, i5-520UM, and i7-720QM. Confusing? Yes. But fortunately, there’s some logic behind the numbers. Let’s simplify matters by looking at what all Core Mobile Chips (CPUs) have in common.

Things All CPUs Have in Common

All of the chips mentioned above come with multiple Hyperthreaded CPU cores that can run at least four simultaneous threads. All of them carry Intel’s Smartcache technology that allocates cache to each CPU core as needed. And every Core chip carries Enhanced Speedstep technology that lets the CPU clock- or power-down areas of the chip to save juice.

Ultra-low Voltage

Some of Intel’s chips go even further in saving power, shipping with clock speeds of around 1.2GHz, compared to the 2GHz-plus you’ll find in normal laptop CPUs. These chips--identified by a U in their processor number--each draw less than 18 watts. You’ll find at least one of them in each of the Core mobile families, and if you’re more concerned with battery life than pure performance, one of these Ultra Low Power chips makes a great choice.

Turbo Boost

While CPU manufacturers have concentrated on multiple cores and parallel processing, software vendors have been slower to make the jump. So while your CPU may be capable of performing four to eight simultaneous tasks, the software you’re running may still be focused on just one.
Enter Intel’s Turbo Boost. This speed-boosting technology detects such situations and ratchets down the clock speed on the core that’s not doing anything, while bumping it up on the core that’s doing all the work. By doing that, Turbo Boosted chips can run a single-threaded load much faster while drawing the same amount of power (and putting out the same amount of heat).

HD Graphics and Clear Video HD

Graphics processing can be one of the biggest power draws in a mobile system, especially in systems with dedicated graphics chips. Intel addressed this by moving HD graphics and video processing onto the CPU itself. While Intel’s integrated graphics aren’t recommended for serious gaming, they can accelerate streaming video and even handle decoding for Blu-ray and other HD video.

Trusted Execution

The ever-expanding danger of viruses and other malware requires hardware as well as software solutions. Intel’s Trusted Execution Technology allows applications to run in their own protected space where code from other software can’t touch them.
So which specific chip is right for you? Here’s a look at Intel’s Core mobile families and how they break down:

Core i3

Chips in Intel’s least expensive mobile processor family run at lower clock speeds, carry a smaller 3MB cache, and lack features such as Turbo Boost and Trusted Execution. Found in lower priced machines, Core i3 chips are a good choice if you’re more concerned with value than performance. Such machines also make good alternatives to netbooks. You’ll give up some portability, but gain a substantial chunk of performance, often for about the same price.

Core i5

Move up to Intel’s midrange mobile line, and you’ll gain faster clock speeds, Trusted Execution, and access to Turbo Boost. That makes Core i5 chips well-suited to mainstream business computing, and a good choice in machines costing in the mid price range category..

Core i7

Intel’s highest-end mobile chips incorporate all the features listed above, and boost cache sizes to 4MB. This line carries the fastest clock speeds among Intel’s mobile chips, and even allows you to trade a bit of clock speed for a pair of additional CPU cores. The i7-720QM and 820QM chips come with 6MB and 8MB of cache, respectively and each carry four Hyperthreaded cores. Those high-end chips are meant to be paired with dedicated graphics processing, so they omit Intel’s integrated graphics.
Core i7 machines are usually in the higher priced bracket, and are capable of replacing most desktop machines. More expensive Core i7 laptops with dedicated graphics can tackle high-performance applications such as HD video editing or high-end image processing.