Answer::If you have more than 512MB RAM and are running Windows 95, 98, 98SE, or ME, you may not have enough cache to handle all of your memory. Solutions to this problem can be found at Microsoft's Web site :
Microsoft has a tendency to change the links to KB articles, so if a link fails to work enter the article's Q number in the search box on the following page. As you can determine from the information in the link itself, the Microsoft link above leads to the article with the Q number of Q253912.
Too much RAM can cause problems with some versions of Windows
Note that if you are upgrading your RAM memory, a computer using Windows 95 or Windows 98 (first edition) will not recognise more than 256MB. Moreover RAM that Windows cannot cache (recognise) will be accessed as slowly as the virtual memory swap file (win386.swp) that Windows creates on the boot hard disk drive to use when the amount of RAM runs out. Therefore, adding too much RAM can slow down a system considerably. Unless you are using a non_Windows operating system such as Linux, and unless you employ the fix a link to which is provided below, your must have Windows 98SE or run a later version to use more than 256MB of RAM.
This limitation does not apply to Windows 2000 and Windows XP.
Moreover, it has now become known the Windows 98 SE (second edition) has trouble with 512MB of RAM and more. Windows 9.x systems were not designed to use large amounts or RAM. Most home users of Windows 9.x are unlikely to require this much RAM in any case, so, if possible, it is advisable to install less than 512MB. If you need to use more, use Windows 2000, or Windows XP, both of which are based on the Windows NT architecture. Windows 95, 98, and Me are based on Windows 95 architecture.
If you have more than 512MB of RAM installed and this causes any problems, you can restrict the amount of RAM used to 512MB (or any other amount) by entering msconfig in the Start => Run box, clicking the Advanced button, and enter the appropriate restriction in the Limit memory to... box - and enable it with a check mark.
There is a configuration file fix that can be applied to make Windows 98 function with as much RAM as you are likely to throw at it. See this excellent article - Windows 98 & WinME Memory Management -
You can also read more about this in a Knowledge Base article Q253912 at Microsoft's site
Microsoft has a tendency to change the links to Knowledge Base articles, so if a link fails to work enter the article's Q number in the search box on the following page. As you can determine from the information in the link itself, the Microsoft link above leads to the article with the Q number of Q253912.