windows - How does UltraVNC achieve "Server Monitor Blanking" -

Ultraven is capable of clearing the monitor of the computer used remotely. My question is how is this possible?

Due to the nature of Windows OS, in my understanding, Remote Desktop applications are limited to displaying only snapshots of limited physical screens. I believe UltraVNC is also subject to this limit.

Any ideas how it is done?

Use force, read.