Beginning with KVM-62, there are more options for high resolution graphics on a kvm guest using standard vga options. This really improves the user’s experience when running a guest using the full screen option and with high resolution. To use this option simply start your guest using the –std-vga option. For example.
qemu-system-x86_64 –hda windows.img –m 512 –std-vga
If you then configure your display options from within your guest you’ll notice that you can specify higher resolutions. For example, within my windows xp guest I can get up to 2560 x 1600 pixels.
You can also combine the full screen option with your high resolution vga by using the –full-screen option so that your guest will automatically start in full screen mode as follows:
qemu-system-x86_64 –hda windows.img –m 512 –std-vga –full-screen
You can toggle full screen mode with ctrl-alt-f keystrokes.
For more on high resolution vga with kvm see Using Vmware vga driver with kvm