5 things a laptop sales person will tell you that aren't true

There are all sorts of things you'll be told when wandering into a retail store looking for a laptop.

Sometimes it's faulty understanding. Sometimes there is no understanding, and they're just repeating what they've been told to say. Sometimes it's wilful misdirection in order to make commission.

Here are some of the things we've heard while shopping for laptops that aren't necessarily true.

...for a limited set of circumstances. The thing is, most programs tend not to take advantage of all four cores on a quad-core CPU. There are specific examples: video encoding, 3D rendering, scientific simulations, artificial benchmarks like counting Pi up to a million decimal places ... but, realistically, after two cores you get diminishing returns for most consumer-level applications.

This is because an application has to be specially written so that it can send a workload to each individual core, which, depending on what the application is doing, may not be an easy thing to program. There are simply some tasks that are most efficient when run on a single core, rather than on four.

As such, this means that a dual-core chip clocked at 2.0GHz can, in many cases, outperform a quad-core chip clocked at 1.8GHz, simply because a program may only take advantage of two cores, and the dual-core chip is faster on a per-core basis.

There's a sub-species of this particular furphy: "it's quad-core 2.0GHz, meaning you get 8.0GHz of power". It's simply not true; you won't magically get 8.0GHz of power in all circumstances to throw at anything you desire.

While there's some code to help spread workload automatically across cores in the operating system, for the most part they don't just magically work in concert; applications need to be specifically coded to take advantage of them. Even then, some cores will only be partly loaded, and some will finish their workload before others. There are applications like Handbrake or 3DSMax that will happily load all of your cores to 100 per cent — but if you're using these programs, then you already know you need as much grunt and as many cores as you can get — if you don't know what they are, you'll likely do fine with a dual-core CPU.

Many programs still only use one core, limiting you, in this example, to a flat 2.0GHz of performance.

Once upon a time, the rule of thumb was to buy a laptop with the fastest processor your budget would allow. This would mean going for the biggest number followed by "GHz" that you could see.

These days, that argument is muddied by a few things: CPU architecture (how it's designed) has much more impact than pure clock speed. That is, a modern 1.9GHz processor will significantly outperform an older 1.9GHz processor. Need proof? Here's a 3.6GHz Pentium 4 being demolished by a low-end Core i3 processor clocked at 3.3GHz.

Then there's Turbo Boost: that is, many CPUs these days can automatically go faster, depending on what's required, up to a set level.

Then there's the big one: most people just don't need super-fast processors these days. In fact, a dual-core, middle-of-the-road Core i5 processor will do perfectly fine, unless you're intending on doing highly taxing stuff like movie encoding or 3D rendering regularly. This is why the whole ultrabook concept works. Even games are more dependent on your graphics card than your CPU.

There are exceptions, but by and large this just isn't the case. You're not actually getting a better physical product — rather, you'll receive a piece of software that attempts to make the cheap, underpowered speakers in your laptop sound better, with mixed results. In many cases, you'll be falling back on headphones for decent audio.

There are some general guidelines that can help you find the best audio solution:

• Check out reviews before purchasing

• If you can find a demo version of the laptop in a store, play some music to test out the speakers

• The bigger your laptop is, usually the better the speakers you'll get. Sometimes you'll even get a subwoofer, but these tend to be in laptops that have 17-inch screens or bigger

• Apple tends to have decent audio across the board

• When there's a speaker brand involved, things generally do sound better. For example, Dell's brief partnership with JBL produced some excellent products, and Asus' laptops with Bang and Olufsen speakers are generally quite good.

When we heard this one, we had to restrain ourselves from slapping the salesperson. It's absolutely false.

There is a side case where having a better graphics card would mean better performance, at least up to a point. If a web developer has decided that they'll make extensive use of HTML5's Canvas feature, or WebGL as developers start playing with browser-based 3D games, then perhaps it could pay off.

But the reality of the situation is that gigantic swathes of websites simply will never ask your graphics card to do anything. Even if you're using Internet Explorer 9, with its hardware-accelerated font rendering, Intel's integrated HD Graphics 4000 will do perfectly fine — you don't need a discrete card from the likes of Nvidia or AMD.

Considering that Intel holds a huge amount of the graphics market (59 per cent in the second half of 2012) despite not making performance chips, your internet isn't going to require dedicated graphics for a very long time. The demand just doesn't exist.

And the speed that your web page loads at? This is mostly dependent on the speed of your internet connection, storage and CPU, and where the website is hosted. The graphics card barely enters into it.

We've also heard the claim that discrete graphics are better for movie watching. Once upon a time, this was true, but it's now completely irrelevant. It is true that a select set of applications outside of games use GPU acceleration; Adobe Photoshop brings some limited advantages, Adobe Premiere becomes a bit more zippy, and a few different video encoders can benefit greatly — but if you're not on the production side of things, and you're not a gamer, you may as well just go with Intel.

In this case, our uneducated salesperson is referring to the video memory, or RAM on the graphics card. A larger amount of memory can allow for things like larger textures in games, or make stereoscopic 3D a bit easier for the laptop to process, but it's definitely not the sole arbiter of performance.

Much more important is the graphics card model, which will have significantly more impact on how your laptop performs.

This in itself can be a minefield, as quite often cards are rebranded. Take the GeForce GT 630M and the GeForce GT 540M — the 630 is better, right? Wrong. The 630 is just a rebranded 540. Want to be more confused? Check out the crazy array of Nvidia mobile cards currently on the market. It's like they're intentionally trying to confuse consumers.

We find Notebook Check to be an excellent resource for clearing up some of the confusion. Find the specs for the laptop you're looking at, then see how its graphics card compares to others in the market.