We get to hear about a lot of new devices at ZDNet and it could scarcely escape our attention that, over the course of the last year or so, the term 'ultrabook' is being attached to a growing number of laptops. But is it just hype and marketing, or is there a real need for a new category of thin and light devices?

Intel introduced the ultrabook category a year ago promising the first machines would be less than 20mm in depth and cost less than $1,000 (£605 at the time, about £645 now). Since then, a number of different manufacturers — Acer, Asus, HP and Toshiba among them —  have speedily launched their own versions in an effort to stake their claim in the ultrabook world. Pictured is the Envy 14 Spectre ultrabook from HP.

However, the definition of what constitutes an ultrabook seems to have widened as the category has matured — with devices up to 23mm thick now allowed to be called ultrabooks if they meet other specifications — leading me to wonder what the real difference between an ultrabook and a skinny laptop really is.

So what does a machine have to do to make it into the ultrabook category? There are specifications on minimum battery life and depth, namely more than five hours and less than 18mm, 21mm or 23mm thick depending on screen size.

However, in its most recent revamp of the ultrabook rules, Intel brought in stipulations that devices running the third-generation Ivy Bridge chip must include USB 3.0 options and Intel's Thunderbolt I/O port for faster data transfers.

Ultrabooks also need to integrate Intel's anti-theft and identity protection technology, as well as its vPro enterprise PC management tools.

All useful stuff, but you don't need to buy an ultrabook to get those specs — prompting the question, is there anything else an ultrabook can deliver that an average laptop can't?

In order to give it the new category a fair crack of the whip, I decided to take a look at two different machines from the same company, one ultrabook and one normal laptop, to see how the two compare.

For the ultrabook, I took a first-generation HP Envy 14 Spectre (left), and for the laptop, an HP DM4 Beats Audio Edition.

Both devices have a 14-inch display, although the Spectre offers a slightly higher resolution at 1,600x900px full HD screen, compared to the DM4's slightly lower-res 1,366x768 display.

On the surface, the two devices were similarly specced. Both had an Intel Core-i5 processor, although the Spectre's is an Ultra Low Voltage (ULV) version. The Spectre also comes with, and can support, slightly less RAM, shipping with 4GB as standard in comparison to the DM4's 6GB RAM.

However, in the ultrabook's favour, the Spectre had a 128GB SSD. In contrast, the DM4 had a traditional 500GB hard disk drive, which should have resulted in faster boot time.

I say 'should' as the boot time for both was abysmally slow, taking literally minutes every single time either of them went to sleep.

I'm putting this down to some sort of software glitch on both machines that is the result of the pounding given to review units. If I'd had more time, or inclination, I would have formatted both, put on a fresh copy of Windows — the pair both shipped with Windows 7 Home Premium — and started from there. However, it occurred to me that, over time, this is exactly how PCs become: slower, less responsive husks of their purchase-day glory.

Given that fast boot times are one of the key factors ultrabooks are being pitched on, the tortoise-slow boot times was a bit of a disappointment. In theory though, an ultrabook should boot faster than a non-SSD equipped laptop.

Pictured is the Envy's backlit chiclet-style keyboard.

Elsewhere, the lightweight, thin design is intended to be another compelling factor in the ultrabook's favour.

Here, too, there was less difference between the two machines than expected: the Spectre is the thinner of the pair, though not by much.

At its thinnest point, the DM4 is almost exactly as thin as the Spectre. Officially, the Spectre measures 20.06mm across the entire chassis whereas the thinnest point on the DM4 Beats Edition was 24mm and the fattest point was 32.3mm. For comparison, HP lists the Spectre's weight as "starting at" 1.8kg and the DM4 as around 1.96kg. Likewise, the company lists the battery life of the Spectre as up to 9.5 hours and the DM4 up to seven hours.

Both devices are Beats Audio branded, making for a fair comparison on audio. 

The Envy 14 Spectre uses a dedicated jog wheel for volume control and hardware buttons for quick access to the Beats Audio software, whereas the DM4 uses keyboard shortcuts accessible via the function (fn) key. There was another small difference between them on audio: DM4 came with a set of over-the-head style Beats Audio headphones included in its price too, the Spectre did not.

That's where the obvious differences stopped: neither sounded notably better than the other, although both were louder than other similar sized laptops that I've used. 

In some regards, mainly the battery life and thinner chassis, the Envy would clearly be the preferable choice, but is it £500 better? No way. In fact, in some ways, the cheaper of the two is actually the better specced: it has more RAM, can accommodate even more RAM and comes with discrete AMD graphics, rather than relying on the Intel HD integrated chipset.

The most compelling reason to choose the ultrabook over its laptop rival was the size of the power pack, as the one that came with the DM4 (pictured) is plain ridiculous for a 14-inch laptop, but how likely is not buying a laptop on the basis that the power pack is a ludicrous size?

And HP isn't alone in its seemingly bizarre specification of its ultrabooks versus its standard laptops. Sony has done something similar the recent launch of its T series ultrabooks, at least one of which is heavier and thicker than its existing ultra-thin Z series laptops.

It's a strange situation: if you have lighter and thinner laptops that, in some cases, cost less than ultrabooks, the term loses any value it had and becomes nothing but branding.

Used well, 'ultrabook' could have differentiated between classes of laptops, immediately telling a would-be buyer that a product bearing the name has certain characteristics. Instead, as the definition of what an ultrabook is becomes more vague, the term has descended into just another buzz marketing word.

For the term to be of any quick reference use, Intel needs to define one key element of the ultrabook and keep it constant. Depth, weight, or price are all key contenders: had it stuck to its £650 ceiling, say, then customers would know, without knowing anything else about the device, that it costs less than this amount.

And it is price that is mostly likely to determine the ultrabooks' future. Last weekend I saw a 48-hour offer on a Toshiba Satellite Z830 13.3-inch ultrabook that brought the cost to £549, a far more middle-of-the-road figure that might tempt me if I were looking to spend around £500 on an everyday laptop. The price has since gone back up to £800, putting it firmly out of the question.

Until the average price falls, ultrabooks are a bizarre anomaly of not-top-of-the-line specs, crammed into small, but not necessarily that light, chassis. For my £1,200, that's just not good enough.

Perhaps the next generation of ultrabooks will rectify this imbalance in some way: HP's follow-up to the Spectre, the Spectre XT (pictured), is due to go on sale in the UK at the end of June, but with a price tag starting from £899, I won't be holding my breath.

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