3D Mark 06: 4,744
Battery Eater: 222
The Acer Aspire S5 is the thinnest Ultrabook right now, and with looks this svelte, it's hard to imagine that record falling any time soon. Yet despite the supremely thin chassis, it still packs a good performance and a decent battery life, matching the MacBook Air in nearly every respect.
Under the hood is a brand new, third-generation Intel Core i7 processor, clocked at 1.9GHz. This is much more powerful than the equivalently priced 13-inch MacBook Air, which only runs an Intel Core i5 processor, clocked at 1.8GHz.
Unsurprisingly, the Acer Aspire S5 produced a fantastic score in our processing benchmarks - one of the highest we've seen on an Ultrabook. It will match many full-factor notebooks for power, and when you consider its size - or lack of - that deserves real respect.
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You can multitask demanding applications, and there's no problem with photo and video editing on the move with this much grunt from the processor.
The operating system felt really responsive, and we rarely suffered pauses for thought.
Graphics fell short with distinctly average performance, even within its cohort of Ultrabooks. There's only an integrated Intel HD 4000 chip onboard, which produced lower than expected improvements over the previous Sandy Bridge family.
You won't be short of power for rich web pages, and you can still make light work of photo editing, and even HD home movies. We played a range of 1080p content without a stutter, meaning only creative types and gamers will feel the limit of the system.
However, with Windows 8 on the horizon, which uses graphics cores to power flashy animations in the operating system, we'd like to have seen a better result to ensure your purchase will last long into the future.
The Acer Aspire S5 is equipped with a 128GB SSD drive, which enables super-fast boot times, and you can expect the system to be responsive in less than 10 seconds.
However, many competitors – including Apple – are shipping larger 256GB SSD drives on similarly priced laptops now, including the top-end MacBook Air.
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This is possibly the first time we've ever been able to applaud Apple for giving great value for consumers, and we'd like to have seen more storage on the Acer Aspire S5, given the £1,249.99/$1,399.99 price tag.
Many super-slim machines opt for a matte screen, assuming you will want to work outdoors where reflections can be a nightmare. The Acer Aspire S5's panel has a resolution of only 1366 x 768, which is inferior to that of the MacBook Air, and it showed. If you want the best ultra-portable display, Apple is the way to go.
That's not to say the display on the Acer Aspire S5 was a mark against its name. The panel is extremely bright, much better than the Asus Zenbook UX31. Images and movies looked sharp, and the Aspire S5 enjoys decent viewing angles. We watched HD movies with no complaints, which is good for a laptop this slim.
In fact, it's so slim that it doesn't seem to be sporting any connectivity ports. Or so its makers would have you believe.
It does actually boast a couple of USB 3.0 ports, HDMI and a 20Gbps Thunderbolt option as well. But to get to these you'll have to uncover the Acer Aspire S5's hidden undercarriage. Or its MagicFlip I/O port panel, as it's officially labelled.
To access the port, you press a button to the right of the keyboard, but our original sample had a problem with the motor, and it wouldn't eject. Acer supplied an immediate problem-free replacement and we had no further problems, but it does feel like a weak point on the chassis, and if this were to happen outside of your warranty, it would be extremely costly.
It's not a reason to avoid the Aspire S5, but if you're looking for robustness, you will want to look elsewhere.
The juiciest of the hidden ports is the inclusion of a Thunderbolt port. First seen on Apple's MacBook refresh from February 2011, this isn't the first time that we've seen Thunderbolt included on a Windows PC, but it's certainly the first time that we've seen the super-fast interface making an appearance at the Ultrabook party.
With such a thin body, the keyboard is afforded minimal travel, which means typing isn't as comfortable as other laptops.
In a shoot-out between the Acer Aspire S5 and the MacBook Air, the Apple wins it for typing comfort, hands down. If you rarely type 1,000 word essays you'll be fine, but anyone looking for a comfortable all-rounder should try before they buy.
The mouse trackpad is an all-in-one, multi-touch affair, which can often be difficult to use. Many of these multi-touch pads can be temperamental to register clicks and presses, and can often result in bizarre behaviour, but the Acer's trackpad was responsive without being over-sensitive, and was easy to use.
Of course, there are some downsides, and the Acer Aspire S5 isn't the most robust laptop we've seen. During transit we noticed a key at a strange angle, which had become dislodged. Pressing it back into the chassis dealt with the problem, but we wouldn't trust it to endure the rigours of life on the move.