Normalne sa to da pouzivat potom ako vo W98 nastavis maximalne pouzitu RAM na 512MB
http://answers.google.com/answers/threadview/id/33 3688.html

On computers with large amounts of RAM, the maximum cache size can be
large enough that Vcache consumes all of the addresses in the system
arena, leaving no virtual memory addresses available for other
functions such as opening an MS-DOS prompt (creating a new virtual
machine).
WORKAROUND
To work around this problem, use one of the following methods:
Use the MaxFileCache setting in the System.ini file to reduce the
maximum amount of memory that Vcache uses to 512 megabytes (524,288
KB) or less. For additional information about how to use the
MaxFileCache setting, click the article number below to view the
article in the Microsoft Knowledge Base:
108079 32-Bit File Access Maximum Cache Size

Use the System Configuration utility to limit the amount of memory
that Windows uses to 512 megabytes (MB) or less.For additional
information about how to use the System Configuration utility, click
the article number below to view the article in the Microsoft
Knowledge Base:
181966 System Configuration Utility Advanced Troubleshooting Settings