If your TV screen isn't detecting the HDMI port your PC stick uses to display your Geckoboard dashboard, try the following steps.
Disable quick boot
If your TV has a quick boot setting, disable it. Quick boot can prevent the TV from detecting the HDMI input on startup.
Check your TV's HDMI-CEC settings
HDMI-CEC allows devices connected via HDMI to communicate with each other. Make sure this feature is enabled on your TV.
HDMI-CEC is labeled differently depending on your TV brand. Samsung calls it Anynet+, LG calls it SimpLink, and Sony calls it Bravia Sync.
Check your PC stick's power settings
Windows power settings can cause devices to switch off when not in use. Make sure your PC stick isn't entering a power-saving mode when the TV is turned off.
Open the Control Panel on your PC stick.
Click Hardware and Sound, then Power Options.
Set the plan to High performance, then click Change plan settings.
Set all options to Never.