32 bit versions of Windows, Including most versions of XP and Vista have a limit of 3.5 to 4 GB of RAM. Although more can be installed, it will not do you any good. 64-bit operating systems can benefit from more RAM, but unless you are a hardcore gamer, video editor, 3D animator, or software engineer, you won't have much use for more than 6 GB right now. Having too much RAM can be a problem on a 64-bit system because the computer has to keep track of all that RAM, when it isn't required. The performance loss is minimal, but not worth it if you spent money on it.