Lag without monitor

I was installed teamviewer on my linux desktop server to remote controle. When i was setting up pc all was okay. After that i disconect monitor and put it neer the wall 2 metrs out of my windows pc. After that i conected linux pc to net and run it. I can connect to server but i have a very big lag. When i connect server to monitor all is okay. Why is that hapen? And can i nerf it somthing without connecting a monitor