Two strange things have happened. The first? The Dell Inspiron M101z is an AMD ultraportable – a hens-teeth rare configuration of teeny tiny processors that could well mark the mainstream resurgence of AMD against Intel's Atom and Celeron processors. It's a decent one at that, as power-friendly as it is powerful.

The second strange thing is that it's Dell that is responsible for this new machine – the same Dell which has been accused – by the New York Times, no less – of a severe Intel addiction, given that it has long seemed to use Intel processors above all else.

Not that putting out such a laptop doesn't make sense, particularly if AMD's shiny low-power Neo architecture can stand up to the rigours of ultra-portable performance against Intel's Celeron and Atom ranges.

This isn't a netbook, of course. No. It's a fully-fledged ultra-portable laptop – albeit a small one without an optical drive – with a titchy screen, and a low power architecture. But not a netbook. No. (Sssh. It is a netbook, just a luxury one. Don't tell Dell.)

Specifications

Let's start with the design. The M101z comes clad in lacquered brushed aluminium, a luxurious 'smudge free' finish that is in fact not smudge free at all. You'll be forever buffing it to remove greasy finger marks.

This almost sticky lacquering continues from the lid – in one of four colours – to the palm rest, and all the way over the touchpad, giving it a slightly-too-grippy feel, but a distinctive classy note. The full-width chiclet keyboard has a surprising amount of travel to it, and it's pleasant to type on.

Dell has chosen an 11.6" 1366x768 screen with a brilliant gloss finish to it, and it's shiny but not full of glare. The resolution is up to the level we'd expect – adequate for most HD videos – but the screen isn't without its issues, as its contrast ratio is frankly awful.

It's one of those panels that doesn't even have a sweet spot. Either the top of the screen is slightly compromised, or the bottom. There's no middle ground, and that's a disappointment.

Of course the big story is the AMD processor, a dual core Athlon II Neo K325 CPU running at 1.3GHz. It's backed in the £499 model on test here by a hefty 4GB RAM, a substantial 320GB hard drive, and the really-rather good ATI RS880M integrated graphics chipset.

The M101z might have netbook-baiting looks, but it's got some serious ultra-portable muscle.

Naturally, given the amount of RAM, it comes running the 64-bit edition of Windows 7 Home Premium and, equally as naturally, Dell has filled it with its own applications.

We could have done without the default application dock – it's a bit pointless given Windows 7's excellent default interface – but the addition of Dell DataSafe backup functionality is a nice touch, particularly for computing newcomers.

Performance

The primary function of an ultra-low voltage chipset is longevity, and the M101z has it in spades. Under light use it's possible to milk a realistic six hours out of its 6-cell battery, and we managed just under four hours when watching standard-def videos on battery power.

That's very good. But that ULV architecture doesn't mean you're sacrificing too much in the way of performance. It comfortably plays 720p videos without a fuss – an essential quality in a modern laptop – and the integrated HDMI socket makes it equally versatile at piping videos to a TV, which is a huge plus.

In a surprise for a machine of this sort of middle level, it has some frankly astonishing speakers. The SRS premium sound setup really makes a difference, and while they're positioned a little awkwardly if you're going to be using the M101z on your lap, you get some booming bass and a real burst of volume if you want it.

Not that you'll need to overcome the sound of the internal fans, since the M101z stays all-but silent until you really tax it.

While HD videos are a viable proposition, gaming is not. The RS880M gives the M101z a measure of 3D performance, but only a very small one.

The Windows Experience Index rates it at 5.0 for 3D graphics, but our experience running 3DMark 06 certainly pitches the combination of processor and graphics chipset a little lower than that. But then it would be a little impudent to expect any more from a machine of this price.

What we need to expect, on the other hand, is value, and the M101z delivers. The AMD chipset trumps the Intel Celeron 743 within Dell's own Insipron M11z in terms of performance, and the high-end model on test here still costs less than the top end M11z. Frankly it's rather excellent value.

If you didn't want the extra muscle you could grab an eMachines eM350, an Acer Aspire One, or even the excellent Samsung NC10 for two fifths of the the price. But we reckon that buying a netbook in the face of a machine like this is a false economy. If you want portability, plump for portability with power.

And, yes, the same money will get you a beefy laptop with a lot more going for it – Acer's 17" Athlon X2-toting AS7751G, for example – but if high end performance is your game, you're going to want to spend a few hundred more.

AMD hasn't really been away from the laptop game, but we think it might have found its new niche with this ultraportable setup. It's just powerful enough that it will remain relevant for a few years to come, but not so powerful that it eats through its battery. Dell has done a great job packaging it, too.

That six-hour battery is pretty astonishing, given the tight form factor of the M101z's case and the amount of power the processor manages to generate.

Videos are slick and glitch-free (although that could probably be attributed to the 4GB RAM in our test model) and there's no problem with Windows 7 performance whatsoever. This straddles the middle-ground between underpowered netbook and over-muscled laptop.

However, the trackpad is almost sticky because of the glossy finish given to the palm rest, and it has spongy buttons – certainly not the sort we'd like to work with for any significant length of time. That pretentious finish might not be up your street either, but that will be a matter of personal taste.

Dell's little software extras remain mostly pointless, although they're easy enough to strip away if you're so inclined. And this isn't a machine to buy for gaming as, well, it can't do it.

Oh, and that screen? The constant contrast issues are very irritating. We really liked this machine, bar a few glaring issues with the monitor.

AMD's Athlon Neo processor is ready for the big time, and we wouldn't even advocate jumping up to 1.6GHz, as it's good enough at this level.

The M101z is so neatly packaged that Dell can legitimately start to compete with Sony on its own territory, and that's quite an achievement.

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