Help ContentsAbout RAM memory settings
Microsoft Virtual PC automatically chooses default memory settings for the virtual machine. However, you can change this setting. The amount of RAM is set for each virtual machine. This setting corresponds to the amount of RAM installed in a physical computer and does not correspond directly to the amount of RAM used by Virtual PC to run a virtual machine.
Low Memory Setting
You may have trouble operating the virtual machine if the memory setting is too low.
The virtual machine may fail to start, or it may start and perform poorly. If you select a value less than 32 MB, which is the lowest recommended
amount for most x86-based computers, Virtual PC will display a warning.
This warning is displayed regardless of the operating system that is installed on the virtual machine, and may not be relevant for the virtual machine for which you are specifying the setting. Some operating systems, such as MS-DOS, may run correctly with as little as 1 MB.
You should determine for yourself the minimum amount of memory required by the operating system installed on the virtual machine. To determine the amount of memory required for a particular operating system, consult the operating system manual.
High Memory Setting
You may also have trouble operating the virtual machine if the memory setting is
too high. Performance may become sluggish to the point of being
unusable. If you select a value greater than the recommended amount, Virtual PC
will display a warning.
This warning is based on the amount of physical RAM currently available on your Macintosh, and may not be relevant when you actually run the virtual machine. For example, shutting down another virtual machine would free up physical memory and increase the memory available to this virtual machine. Conversely, starting another virtual machine would consume physical memory, and reduce the amount available to this virtual machine.
You should determine for yourself the optimum memory setting for each virtual machine. When running more than one virtual machine, it is not advisable to select the highest possible setting for each virtual machine.
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