One of the factors which makes or breaks your purchasing decision is the form factor. Every form factor is different, but there are many things you can learn about a form factor before you buy it. A great new model can have severe drawbacks if it's not fit for purpose.
There is something that most computer users agree on when they talk about the ergonomic form factor. Many people have spent countless hours trying to fit the computer into a form factor that will provide the best experience possible. And if you look at what's important to most people, you'll see that it's not the computer itself, but the experience that matters. The display is very important, but the real issue is the user experience.
The most compelling element of the ergonomic form factor is the lower center of gravity. These form factors seem to be more comfortable to use than any other form factor, and they have many other advantages as well. Because the screen is higher off the floor, the mouse and keyboard can be lower to the ground, reducing their angle of attack.
Of course, most users get used to this comfort in a natural sense, but a feature that has been popular for decades is the desk with adjustable legs. In this case, you can adjust the height of the computer desk to fit your needs.
The design also allows for the use of mechanical drives, which provide better performance than magnetic disks, and are easier to keep clean. Because of their size, however, mechanical drives are less portable than the other two options.
Having a low center of gravity also means that the computer has less inertia, and therefore the peak efficiency is achieved at a lower speed. This is why the mini-ITX form factor is so popular.
Because of these advantages, you can achieve significant power savings and operational costs with the one form factor. You can also reduce the volume of cooling you have to do by using only one form factor. This makes them much cheaper to build and to run, as well.
On the other hand, just like any other device, there are disadvantages to having multiple devices. Because it is possible to end up with too many moving parts, it can be possible to overload the system. Also, there may be space requirements that are impossible to meet.
To help avoid this situation, you should think about whether you're going to buy more than one device, and what you want it to do. For example, you might think about buying two identical graphics cards in case you upgrade later. You might think about buying two identical computers with different components, or maybe just one computer and a separate display card, and just getting the graphics card later.
Because we've established that form factors come in many sizes, there are a few that you should probably avoid, though. The first is the cube design, which is really only a form factor to begin with. There are many cases out there that you might consider, but only a few that are actually suited for it.
The other thing you should avoid is the full desktop form factor. This is really only suitable for very large or very expensive computers. You should look instead for a laptop desktop form factor, which is usually portable enough to be carried around in a briefcase.
With all of this information, you should now be armed with the knowledge you need to make an informed decision. Knowing the benefits and drawbacks of each form factor can give you an idea of what will work best for you.