HDMI to mini display port adapter not showing a picture. Says active.

Problem solved! Thanks

New monitor works with VGA to DVI port adapter but does not work with HDMI to mini display port adapter. It is a passive cable. No need to have audio. The VGA cable appears to be falling so I went to a new cable to a different port with a newer HP23es monitor. Looked in preferences and no way to switch ports from the computer inself. Late 2009 model.