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Development: UltraVNC development is always here... Any help is welcome
Feedback is welcome
A new stable version, UltraVNC 1.6.4.0 and UltraVNC SC 1.6.4.0 have been released: https://forum.uvnc.com/viewtopic.php?t=38095
Feedback is always welcome
2025-12-14: 1.7.1.X-dev release builds need tests and feedback: https://forum.uvnc.com/viewtopic.php?t=38134
2025-12-02: We need help: English Wikipedia UltraVNC page has been requested to deletion: https://forum.uvnc.com/viewtopic.php?t=38127
Any help is welcome to improve the UltraVNC page and/or to comment on the Wikipedia Talk page
2025-05-06: Forum password change request: https://forum.uvnc.com/viewtopic.php?t=38078
2023-09-21: Important: Please update to latest version before to create a reply, a topic or an issue: https://forum.uvnc.com/viewtopic.php?t=37864
Development: UltraVNC development is always here... Any help is welcome
Feedback is welcome
Why is UltraVNC Server drawing CPU time when no connections?
Why is UltraVNC Server drawing CPU time when no connections?
My UltraVNC Server executable draws from .1 to .6% CPU continuously, even when there is no connection. I don't know if this is the service instance or the UI instance, but if the UI isn't being manipulated, what is it doing? Is it periodically polling the service?
- Rudi De Vos
- Admin & Developer

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Re: Why is UltraVNC Server drawing CPU time when no connections?
The service poll the desktop to see if the logon changed and the desktop part require a restart.
But this should use a lot of cpu,
The desktop part also monitor the systray, to show the systray icon when available. ( this is done every 5 seconds)
Active VNC server logging, perhaps you see some indication of what the server is doing
But this should use a lot of cpu,
The desktop part also monitor the systray, to show the systray icon when available. ( this is done every 5 seconds)
Active VNC server logging, perhaps you see some indication of what the server is doing
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