As applications become increasingly memory-hungry, a computer without enough RAM will quickly hit its limit. Because no matter how fast the processor or hard disk might be, insufficient RAM will slow down the whole system.
If you're thinking of upgrading an older computer, you may have to take memory management limits into account. Computers running the outdated Windows XP or Windows Vista operating systems, or the 32-bit versions of Windows 7, Windows 8 and Windows 10 can only manage 4GB of RAM.
Finding out how much memory you have in your computer is easy. In Windows 7, go to the start menu and call up the system information with a right click on "Computer" and then "Properties". In Windows 10, the overview can be found in the Control Panel under "System".
Programs like CPU-Z are even more effective. The free software not only provides a comprehensive overview of installed hardware, it also lists exact data on the memory used. This is important to make sure that you'll be able to buy the right memory modules. Your manual will also tell you which modules the computer's motherboard supports.
The speed is usually higher if two smaller memory modules are used instead of one large one – for example, two 16GB instead of one 32GB. The experts also advise paying attention to ensure correct installation. In most cases, the memory slots intended for installation in pairs are marked in colour.
If not, two modules that belong together should be plugged into the first and third slots from the processor's perspective. If you purchase more memory modules later, you can plug them into slots 2 and 4. – dpa
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