I suggest trying the following steps to troubleshoot and hopefully resolve your issue.
• Check for driver updates
• Check for OS updates (i.e. Windows update)
• Prioritize your GPU settings for Steam & SteamVR to Maximum Performance
• Verify the integrity of your SteamVR install
• Check that your Lighthouses are set up properly and are ready for tracking
• Check for updates on your components (i.e. Headset, Controlers, Lighthouses)
Hopefully one of these will resolve your issue. If not you can respond here, and I or another member will try to assist you further.
If you still need help or have further questions, reply in the forum and I or another member will attempt to help you ASAP! _____ I am NOT an HTC or Valve employee. If I have helped you or resolved your issue, please accept my answer as the solution. _____ "Welcome to the world of VR" -Mango