You should refer to the product documentation included with each operating system to determine the minimum system requirements for the guest operating system. Be aware that the minimum required disk space you need is the sum of the required disk space of each guest operating system and the host operating system, in addition to disk space for any applications to be installed on the operating systems.
Windows Vista will run on a computer with a minimum of 512 MB of RAM
128MB of ram
Because this method generally works best when the difference between the minimum amount of RAM you can order and the amount desired is quite big.
it should be minimum 2GB
Minimum is the amount you need just to use it. Recommended is the amount it is advised you have for best performance.
375 MB
Snow Leopard requires 1GB minimum of RAM. For generally smooth operation, you'll want to go with 2GB. For a more robust setup, go with 4GB or higher. 256 MB
Minimum system requirement is the minimum amount of processing speed/ram/video processing (other) that is required to run a program/game/OS/everything. Go to both Google and control panel\system\hardware\device_manager to video and right click my computer. (assuming/all providing you are using windows)
two
System Properties Window
The amount of RAM in a system has no bearing on the size hard drive you can use.
The minimum amount of RAM you should be looking for in a new notebook running Windows 7 is 4 GB. You can read more information at compreviews.about.com/od/memory/a/Vista4GB.htm