virtualbox.org

this might be a stupid obvious answer, but the RAM you allocate to the Virtual System is only used when Virtualbox is open correct? I have a Mac with 2gb of memory and allocated 1gb to virtual windows 7 system. That means when Virtualbox is in use it gets allocated that 1gb of memory, or is it completely given to it even when not in use?
Just wondering because ever since installing Virtualbox with Windows 7, my Mac seems laggy and the internet is jumpy.
Thanks.

Yes. When you have a VirtualBox VM running, like the VM you created for Windows 7, it will use all the memory you allocated for the VM. When you shut down the VM, it will return that memory to the host (OS X).

cool, that's exactly what i wanted to know, thanks a lot!