Ubuntu has established a tradition of releasing a newer version of their software within every six months, which is usually during April and October. This brings about a pertinent question that you should ask yourself. Is it really necessary to upgrade your pieces of hardware every six months in order to receive more features? In order to take advantage of the upgrades without unnecessarily spending your hard-earned cash every now and then, you should be aware of the needed system requirements.
There are basically three versions of Ubuntu, namely, server edition, desktop edition, and netbook remix. As the name of this newest edition indicates, it is primarily intended for netbook users.
Although it is actually possible to install Ubuntu on an Intel 486 processor, there is hardly any use in doing this. This is because all you will get is a white blinking cursor without any graphical desktop. Even though you may be interested in using it as a local print server, I advise you against this, since it will not be easy to get necessary components in case of a breakdown.
In such a case, it is better to use the server edition instead. You will require fairly low system requirements, with no graphical environment. My recommendation is a minimum of Pentium 3, with 256 MB RAM for optimum performance.
However, in order to make the most of Ubuntu, you will need more than your old PC. For instance, if you want such special effects as 3D cube that rotates across the screen, or wobbly windows among others, you need to have a 3D accelerator card. This calls for newer PCs and laptops.
Another thing to take into consideration apart from the graphics card is the RAM. In order to have an appealing desktop, you will require at least 1 GB RAM.
Unfortunately, there was not much option for netbook users. In spite of upgrading hard drive and RAM, it is still not possible to have all the features of the desktop edition. This is where the netbook remix comes in handy.
Although I'm pretty sure that there are still other Ubuntu upgrades in the pipeline, the minimum system requirements will remain the same. This knowledge will save you from unnecessary upgrades.