Intel Centrino Pro and Duo review

Whether the first Centrino release was a response to or an effect of the rapid growth in the notebook's popularity at the time, it provided the first consensus of targeted mobile computing improvements - battery life, wireless connectivity and overall performance.

Now these feature improvements have been bolstered and added to, with, at launch, two distinct flavours of the latest Centrino. Centrino Pro targets the business user whereas Centrino Duo is for everyone else. There's talk of a Centrino Duo Extreme Edition to follow, catering for the gaming community with less emphasis on battery life and more on speed.

The perennial choice between a desktop or laptop may no longer depend on price and performance but instead on what the desktop lacks and the laptop has gained.

Turbo Memory is a case in point. The NAND flash memory hard disk enhancement technology vastly improves performance. It also promises to extend both the battery life and the life of the hard disk itself as it reduces the amount of read/write activity on the platters.

Turbo Memory is a fundamental change to data storage and the bottom line is that you will want it, especially as it will only add at most around £15 to the cost of a new Centrino laptop.

For performance improvements alone, Turbo Memory will make it onto desktop PCs at some point soon, but its effects on battery life will not be realised. And it's the overall contributions to battery life extensions that's most evident with Centrino's release.

The new GMA X3100 graphics chipset, released alongside the new Centrino, is designed with a maximum overall laptop TDP (Thermal Design Power) limitation of 35W. It achieves this with several new battery saving features including support for D2PO panel intensity dynamic adjustment as well as display refresh rate switching, which reduces the need to redraw an image on a screen when it's not moving.

However, GMA X3100 is not required for the Centrino badge, and you will find better performance elsewhere.

If battery life is a crucial factor in your choice of laptop, then along with the power-saving enhancements of the X3100 and Turbo Memory, you also have new SpeedStep enhancements.

A new processor sleep state, known as DC4, shuts down large portions of the CPU during idle periods with occasional interrupt request sweeps to see if it needs to wake up. A new lower active state allows for a change in bus clock frequency, so battery life is longer when playing DVDs and music.

We found this happening when comparing two laptops with the new platform, one sporting a Turbo Memory drive (and DC4 support), and one without; we noticed the positive difference on the fully-tooled machine, which lingered at 94 per cent battery as its opponent was 90 per cent.

The end of the line was similarly positive; the DC4-enabled machine managed an extra 16 minutes life over its otherwise identical brother.

The graphical TDP changes didn't exactly show themselves with much clarity, however. The top time on our white box systems, playing visualised MP3s in Media Player, was a mildly disappointing 137m 30s; whether commercial implementations of the mobile 965 chipset can squeeze a little more life out of the package is so far unclear.

Dynamic processor core speed changing is also used as part of the new single core Turbo Mode boosting. In all models of Core 2 Duo from 1.8GHz, one of the cores can jump in clock speed by up to 0.2GHz in response to a single application's need, and all still within the 35W TDP.

This process is synonymous to the way in HyperThreading used to work - the active core takes the extra TDP headroom from the idle core to gain the increased performance.

The new Mobile 965 Express chipset family brings support for the new sleep states and dynamic speed switching of the enhanced mobile Core 2 Duo. There's also increased Serial ATA I/O bandwidth at 3Gbps, extra USB 2.0 port support and the Matrix storage controller improves its rapid recovery technology.

The differences between the Pro and Duo versions of the new Centrino can be summed up as additional security for and control over the Pro user. Remote administrator services are also enhanced with Intel's version 2.5 of its Active Management Technology (AMT) bringing additional over-LAN firmware addressing functions for diagnostic discovery, healing and protecting.

To receive the Pro brand over the standard Duo, Intel's 82566MM Gigabit Networking Connection with AMT 2.5 firmware and a Virtualisation Technology capable BIOS should be present. Both wired and wireless LAN management is capable.

With several wireless technologies, Intel has made some judgement calls as to which integrated support would be most suitable. It already called off support for 3G on pricing grounds and WiMax wasn't quite ready - if you require these, then both can be added later through either ExpressCard of mini-card PCI Express add-on boards.

The new Wi-Fi Link 4965AGN provides quad A/B/G and draft-N support giving you the maximum currently available data transfer speeds, MIMO (multiple in/multiple out) support, as well as the added bonus of support on the less-used 5GHz bandwidth when using 802.11a.

To quash any doubts over pre-ratification support for draft-N, Intel has undergone interoperability tests with major wireless kit manufacturers producing the 'Connect with Centrino' badge which will be on kits that pass the test.

How does overall laptop performance now fare under this revision? The Front Side Bus gets a speed hike to 800MHz. Yes the desktop is currently dizzying at 1066MHz, but again a 35W TDP is Intel's target here and maybe an Extreme Edition will be allowed to burst through this barrier.

Performance, despite the massive amount of wattage shaved, was as we'd expect for a system of this strength. Though Vista has proven to make our more reliable benchmarks curl into a ball, we did get a good showing out of PCMark 04.

The better of our two test machines did its job perfectly, utilising Turbo Memory to extract an ever-increasing benchmark score; by the fourth run, it earned 4114, a fraction higher than the non-TM score of 3981.

Unlike other Centrino releases, this new platform doesn't come with a new processor revision, but this doesn't matter. Now Centrino defines the laptop platform of choice with a set of features designed to attend to the needs of mobile computing.

With this release, Intel's lead over AMD and VIA has extended with only the cheapest of laptops likely to feature non-Intel CPUs. But for any laptop user with needs beyond the most basic of requirements, only a Centrino laptop will do.