I have an Intel motherboard (DH67CL) that uses Intel HD 3000 video. It has two video output ports: HDMI and DVI. Both my monitors are DVI, so I have two cables: a DVI->DVI and an HDMI->DVI.
If I plug a monitor into just one of these ports, things work fine. However if I plug monitors into each of the ports, the system startup screens show on both monitors, along with the "Starting Windows…" screen, but as soon as the system boots into Windows, the HDMI-connected monitor goes to sleep.
When I use the Intel video control panel, the HDMI-connected monitor is not detected. How do I get a dual-monitor setup to work?