At the heart of the Aspire 5551 beats AMD's latest 35W tri-core mobile CPU, the Phenom II X3 N830. Its clock speed ranges between 1.8 to 2.1GHz depending on load, and it sports 512KB L2 cache per core. It is cleverly positioned to fill a perceived gap in Intel's line-up: that of a mobile processor with more than two physical cores at a relatively 'budget' price point. However, we have to wonder whether the extra core and its concomitant power draw are worth it for the average consumer, who is unlikely to run many heavily multi-threaded applications on the laptops the N830 is liable to find itself in. Still, it's impressive that AMD has added an extra core without raising the wattage from its previous dual-core offerings.
In our PC Mark Vantage runs the Aspire 5551's N830 was consistently beaten by the previous-generation 2.5GHz, dual-core AMD Turion II Ultra M620 found in the cheaper HP Pavilion dv6-2113sa (logical considering the M620's higher clock speed), while the Core i5 found in the more expensive Aspire TimelineX 4820TG simply wipes the floor with it. If you run multi-threaded applications that will truly take advantage of the third core then this might be the mobile CPU for you, but for most people's use the N830 will be outperformed by cheaper dual-core alternatives.
Unfortunately things don't improve when we get to the graphics. The Mobility Radeon HD 4250, with its miserly 256MB of RAM, is certainly no gaming card - as you can see below.
In fact it's not that much more impressive than Intel's integrated graphics efforts, in that it too won't allow you to play even basic 3D games like TrackMania Nations Forever at decent settings. Still, it does a good job of video acceleration and processing, taking that load off the CPU.
Battery life from the Aspire 5551's 4,400mAh/48Wh lithium unit is reasonable, and it's good to see that, in the intensive DVD test at least, this Aspire isn't suffering from its processor's extra core.
In fact, in the Productivity test this Aspire held up better than many similar laptops with older dual-core AMD processors, managing a full 3hrs and 21mins. However, raw horsepower is not the only benchmark where the 4820TG's Core i5 wins the day, as battery life is also significantly better.
This brings us neatly onto our value considerations, where unfortunately the new Aspire 5551 doesn't hold up too well unless you really need its CPU's third core. If you can afford an extra £150, the lighter Aspire TimelineX 4820TG is well worth the larger outlay, offering better build quality, battery life and general performance in applications and games. If you're on a limited budget, the award-winning HP Pavilion dv6-2113sa is a better bet at just £540, with its lesser battery life offset by more connectivity and features (including ExpressCard, Firewire and Bluetooth), a larger hard drive and better performance. If battery life is a prime consideration, Dell offers an Inspiron with a Core i3 CPU and Radeon HD 5450 graphics with Bluetooth for £550, while upping this to £630 will get you a Core i5-based Studio 15 with a Radeon HD 5470 and larger 500GB hard drive.
While the new N830 Phenom II X3 mobile processor doesn't use more power than previous dual-core AMD chips, its performance isn't stellar unless you really need more than two cores. Lacking any other distinguishing features, this version of the Acer Aspire 5551 thus feels like a cheaper laptop than it actually is and, until its price comes down, there are many more attractive options readily available - even from Acer itself.