This question really depends on what kind of computer you have and which operating system you are running. In general, the more RAM the merrier, but you should be aware that there are both hardware and operating system limitations that will ultimately become the deciding factor in your upgrade decision. For example, many computers that shipped with Windows XP can be upgraded to no more than 2 GB of RAM because of limitations with the PC’s motherboard. Also, Windows XP is only capable of using 3 GB of RAM. So even if your PC’s motherboard could for example handle 4 GB of RAM, Windows XP would only be able to utilize 3 GB. Please see the list that I have made below of recommended memory configurations by operating system.
Many of the computers from the Windows XP era shipped with only 256 MB of RAM installed. Fortunately however, a large portion of these machines are capable of being upgraded to 2 GB of RAM. If you are happy with your Windows XP computer but wished that it would run a little bit faster then I would highly recommend that you consider upgrading the RAM in your PC. I have upgraded the RAM on hundreds of Windows XP computers and noticed incredible performance gains each and every time.
Although Windows Vista requires a minimum of 512 MB of RAM in order to operate, it really should be equipped with 2 GB of RAM or more in order to work well. Some retailers offered “door buster” deals on laptops at the time of Windows Vista’s 2007 release. Many of these laptops came with only 512 MB of RAM installed. If you purchased one of these underpowered laptops I would highly recommend that you upgrade to 2 GB of RAM.
Windows 7 requires a minimum of 1 GB of RAM in order to operate. I installed Windows 7 on both a netbook and a Parallels virtual machine each with only 1GB of RAM installed and Windows 7 ran quite well in both instances. Windows 7 really shines on a 32 bit computer with 2 GB of RAM installed and is absolutely mind blowing on a 64 bit computer with 4-6 GB of RAM installed. Some professional applications can benefit from 8 GB of RAM (or more) installed but these applications are typically not used by the average user.
Mac OS X
Consumer Mac products such as the Mac Mini, MacBook, and iMac run best with 4 GB of RAM installed so make sure that you select this option while you are ordering your Mac computer. The MacBook Pro and Mac Pro should be ordered with enough RAM to satisfy professional application requirements. This could mean that you may have to configure your professional Mac computer with more than 4 GB of RAM.
How Much RAM Do I Have?
Now that you know how much RAM you should have, you’ll want to know how much RAM you do have. To do this, simply right click on the My Computer icon and left click properties. You’ll see the amount of RAM that your computer has displayed at the bottom of the System Properties page.
If your computer has the recommended amount of memory but is still running slowly, it is possible that your computer may have a spyware infection. You can use my Spware Removal Guide to remove spyware from your computer.