This sounds an awful lot like a problem I had with a VNC server a long time ago, on Windows. After a lot of frustration it turned out to be a configuration issue. The VNC server was polling too zealously - constantly polling the entire desktop, instead of a more effecient strategy like polling the area under the cursor and a small surrounding area, and polling the rest of the desktop only periodically. All this polling was a real drag on CPU resources, and a pretty easy configuration change fixed it. I haven't used VNC in a long time, so I don't have any more specific advice off the top of my head, but hopefully this info will be useful.
-- VNC much slower with kubuntu client than with vncserver https://launchpad.net/bugs/67165 -- kubuntu-bugs mailing list kubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/kubuntu-bugs
