They tend to use older OSes (and older software in general), that tends to be more unstable. For example, Windows XP froze a lot less than Windows 95/98. Plus, older software tend to be unmsintained. read more
Adding any type of hardware such as a new video card or even a sound card could also cause your computer to freeze. The best thing to do is to remove the piece of hardware. If this is the reason, make sure of compatibility with your computer, especially if it's an older model. read more
When people refer to computer freezing, they typically mean that computer system is unresponsive to any user action, such as typing or using a mouse on the desktop. In a nutshell, freezing means that nothing happens. Generally, it does not mean that computer is broken, but rather that processor encountered an overload that cannot be handled. read more