HTPC mode explained

The short explanation

When a display disappears, Windows decides that screen is gone and moves everything on it to a remaining one. Turn the display back on and the layout does not come back. Anyone running a PC into a projector or television has met this.

HTPC mode is meant to address it at the HDMI level, so the PC is not thrown by the display going off or coming back from standby.

Where you run into it

If your source is a PC, this is the difference between a machine that behaves and one that reshuffles itself every time the projector goes to standby. If your source is a player or a console, the setting is irrelevant.

How the DR HDMI 8K handles it

HTPC mode is a switch on the DR HDMI 8K's CONFIG page. One important limitation from the manual: HTPC mode is not compatible with an HDCP signal, so it is a setting for desktop and application use rather than for protected playback. The separate TX +5V force option is a different tool: it decides whether the unit detects the display at its output at all.