Notes on display handling / optimization under kvm.
As of June, 2009, video support is pretty weak in kvm/qemu. If you are planning to run games or graphic intensive software on your guest you will probably not get the results you are looking for.
opengl, directx etc
Interactions with host display drivers: fglrx
The emulated video adapter appears to be controlled with the command-line switch: -vga [std|cirrus|vmware|none]
Cirrus Logic 5446
This is the default guest adaptor (at least in my version of kvm). It has limited memory and resolution settings.
If you can get your guest to display at the same resolution as your host display, you can run in full-screen mode with no scaling artifacts. This allows you to use your guest display almost as if it was a real display. Unfortunately, the default emulated video adapter (Cirrus Logic 5446) may not support the resolution you want.
sooooo