I'm trying to set up a dual monitor machine with an Intel DH67BL motherboard, Ivy Bridge i5-3450 CPU and dual Samsung 204b monitors.
I can't seem to get the computer to recognize more than one of these monitors at a time.
I can get either monitor to work using the DVI port directly or with a DVI-VGA cable, or by using the HDMI port with an HDMI-DVI cable.
I managed to sort of get them working by substituting 2 smaller monitors and hot-plugging to the 204b's, but this locked me into an appallingly low resolution, and broke as soon as I tried adjusting the resolution.
KDE's display settings only shows whichever monitor is currently working as connected.
The Samsung 204b's also appear to be outputting bad EDID information, so forcing monitor settings is probably going to be necessary.
Edit: I ended up adding an old nvidia card to the computer, which runs both monitors quite happily.