Computer performance depends greatly on the availability of RAM memory. PCs will work with little ram memory but when all the RAM is used, Windows will have to use virtual memory which is stored on the hard disk and is much more slow.
When installing or replacing RAM memory modules it is very important to get the right modules. There are many models, speeds and different technologies and if we make a mistake we may destroy the whole computer and some modules work at different voltages. Also there are some compatibility issues depending on the brand, and it is important to take this into account when buying ?a new memory module.
Windows XP will work with only 256MB but at least 1GB is recommended, if you install 3GB it will fly. Windows Vista and Windows 7 need a minimum of 1GB but 2GB or 3GB is recommended. If you have a 64 bit version installed you will be able to install up to 2TB (2TB=2,000GB=2,000,000MB) on some Windows versions.
Sometimes the RAM memory modules can be quite difficult to access, on some laptops it is under Keyboard, which requires professional?disassembly techniques.