I'm upgrading all of my home pc to Win 8.1 and I've run into a perplexing issue. Maxent monitor won't display anything once the OS gets to the lock screen. Bios and blue windows loading screen shows up then goes blank when the lock screen comes up, message displayed by TV says "No Signal". I've tried this with two different pc's with the same result. Video drivers are up to date as well as OS. PC start up fine and I can RDC into them and Display options cannot be changed while logged in.. Win 7 Home Premium worked fine on the same monitor and PC. PC also works on regular monitor.

Would like to know some information about the issue so that we could help you better.
1. What is the make and model of your computer?
2. Does mouse cursor appear when you say, "goes blank when the lock screen comes up"?
I appreciate you for providing details about the issue.
This issue may occur due to corrupt display adapter driver.
I would suggest you to uninstall and reinstall display adapter driver and check if it helps.
Step 1:
Uninstall display adapter driver. Please follow these steps:
a. Press Windows + X keys and click device manager.
b. Expand display adapters.
c. Right click the display device and click uninstall.
d. Restart the computer, if message prompts.

Step 2:
Reinstall display adapter driver from the manufacturer's website and check.