VirtualBox causing big peaks in CPU

[Chris Jones]

> Too _much_ memory.  Win XP shouldn't need 400Mb of memory in VirtualBox, and
> that's (virtual) memory that will no longer be available to your Linux
> tasks.  So you get swapping, and CPU usage.

That entirely depends on a) how much ram the host machine has and b) 
what else it is doing whilst it is running the VM with 400Mb ram. If the 
conditions are right you can give a VM as much ram as you want...

Chris