Santa Rosa: Crave goes hands on with the new Centrino

Good news laptop fans, we've got a Santa Rosa laptop, and we've been putting it through its paces for the last few days. What is it? Why should you care? Read on to find out!

Santa Rosa is the codename for the latest iteration of Intel's Centrino platform. It's been in development for several years now under the codename Santa Rosa, but will be known as Centrino Duo in consumer laptops, or as Centrino Pro for business machines.

Nerdy as it may sound, this is a pretty big deal. The original Centrino platform very much revolutionised the laptop market in 2003 by promoting the message of long battery life and ubiquitous wireless connectivity. It's arguably the reason millions of you can sit in a Starbucks sipping macchiatos and catching up on emails. Without it, you'd probably be running around boasting about how wonderful your desk-bound 5.2GHz Pentium 9 is, not caring about Wi-Fi or battery life.

Santa Rosa improves on its predecessor by bringing several innovations to the table. Unlike many of our rivals, we've been testing them on a real Santa Rosa laptop and can now tell you, exclusively, how this will (or won't) benefit you. With numbers and everything.

Update: A full review of a Santa Rosa laptop is now live.

Core performance
Santa Rosa laptops will feature a series of all-new CPUs, which are designed to run faster than their predecessors. Like the older model, the new chips will (initially) be dual-core and feature 4MB of on-die cache, but while the old models utilised a front-side bus speed of 667MHz, the new chips have an FSB speed of 800MHz. The faster the FSB, the faster the processor can shuttle data to and from the memory subsystem.

Obviously, cranking up the FSB will have a detrimental impact on battery life -- which is completely against the Centrino philosophy. To mitigate this, Intel has added dynamic FSB switching, so it can throttle back to a lower frequency when running light tasks like playing a DVD or music.

Better still is the new Dynamic Acceleration. This enables single-threaded applications (those that don't take advantage of both cores in a dual-core CPU) to run more efficiently. Santa Rosa can shut down the inactive core and increase the clock speed on the active core in order to boost performance and save battery power.

Intel will also introduce a feature called Turbo Memory, which is designed to speed up boot times and application responsiveness. This is essentially a piece of NAND memory (either 512MB or 1GB in size) mounted directly into the motherboard, or into a special slot should the laptop manufacturer choose. It works in a similar manner to Vista's ReadyBoost, but is faster because data transfer speeds aren't limited to USB's maximum of 480Mbps. Plus, unlike ReadyBoost, it can be used outside of Windows, so it can speed up boot times, plus it doesn't have to waste valuable juice powering a USB device.

Crave's test results
The 2.2GHz Intel T7500 Core 2 Duo chip in our Santa Rosa laptop, paired with 1GB of DDR2 667MHz memory, helped our Santa Rosa sample achieve a PCMark 2005 score of 4,312. It's not exactly mind-boggling, but it's very solid and with time, we expect to see laptops achieving higher scores than this. For reference, the Dell XPS M2010 scored 4,112 with a 2GHz CPU, and Alienware's AMD Turion 64 Mobile ML40-equipped m9700 laptop scored 3,441.

Graphics performance
The Intel 965 chipset in Santa Rosa laptops delivers fairly potent graphics performance -- for a laptop. Many laptops will utilise the integrated Intel GMA X3100 graphics chipset, which is DirectX 10-compatible. In many ways this card is like the Xenos graphics chip at the heart of the Xbox 360, as it uses a unified shader architecture. In reality, it's nowhere near as fast as the Microsoft console, but it supports HDMI output with HDCP compliance, and has Intel's Clear Video technology, so you get smoother hi-def video playback, sharper pictures, and more control over colour and contrast settings.

Santa Rosa also does clever things to the display in order to stretch out battery life. It does this by changing the 'refresh' rate on the display. Sure, LCDs don't have a refresh rate as such, but the new Centrino platform can reduce the number of times per second the liquid crystals are twisted or untwisted -- thus reducing power drainage and increasing battery life.

Crave's test results
We can't tell you how good Intel's X3100 chip is, since we don't have one. Our Santa Rosa sample uses an Nvidia GeForce 8600M GT with 512MB of RAM, which by our reckoning is a faster solution. We tested it with 3DMark 2006 and it achieved 3,668, which is excellent for a laptop that isn't designed to be a gaming machine. It helped F.E.A.R run along at 29fps at a resolution of 1,024x768 pixels, with all the settings cranked to maximum, and 4x FSAA and 8x AF enabled.

Battery life
We've already learned how dynamic FSB switching, dynamic acceleration and Turbo Memory all contribute to prolonging battery life, but there's more. Intel has added an 'Enhanced Deeper Sleep' idle state, which lets the Core 2 Duo CPU go into super-lazy mode when it isn't doing anything.

Crave's test results
With every new generation of laptop, Intel generally strives to increase performance while keeping battery life the same, or extending it slightly. That again seems to be the case with Santa Rosa. Our test laptop scored highly in core performance and graphics tests, yet its battery life is solid if not mind-boggling. It lasted 74 minutes in our BatteryEater test, which is very good considering how quick it is.

Wireless capabilities
The new Centrino supports all the usual 802.11b and 802.11g Wi-Fi networks, as you'd expect. But Intel has upped the wireless ante by adding support for the draft 802.11n standard. Unlike 802.11b and 802.11g, which offer connection speeds of 11Mbps and 54Mbps respectively, 802.11n goes to a monstrous theoretical maximum of 300Mbps.

Santa Rosa laptops will use Intel's new Wireless Wi-Fi Link 4965AGN card, which is said to use less power than Intel's previous Wi-Fi cards. It also uses MIMO (multiple in multiple out) trickery, where multiple data streams are sent concurrently in order to boost throughput.

Crave's test results
300Mbps sounds awesome, but you'll never achieve that kind of transfer speed in the real world. We'd expect it to perform in line with a 100Mbps wired Ethernet, which is still pretty good compared to clunky old Wi-Fi.

It's worth noting that in order to be MIMO-ready, your new Centrino laptop needs to have three antennae built into the chassis. Unfortunately manufacturers can gain Centrino accreditation with just two antennae, so MIMO is not guaranteed across the range.

Verdict
The future is definitely bright for Centrino. Santa Rosa is more of an evolution than a revolution, but the improvements to power management, speedier graphics performance, and the solid (if unremarkable) battery life give us hope that the next generation of Centrino laptops will be much more flexible (and fun!) than the current crop. -Rory Reid