I've had a 2012 Mini for about six months - I just replaced one of my displays, and now a different display does not go into power savings mode properly. Mini is running 10.9.2. Old config: DP->HDMI adapter->HDMI cable->Samsung BX2450 HDMI port->HDMI/DVI cable->Samsung T260 USB->DisplayPort DVI->DVI/HDMI cable->Samsung BX2450 All three displays would power off their back lighting when the mini puts the displays to sleep (the mini itself is setup to never sleep). New config DP->DP Cable->HP zr2740w HDMI port->HDMI cable->BX2450 USB->DisplayPort DVI->DVI/HDMI cable->BX2450 Now when I go into display sleep, the monitor attached to the HDMI port behaves as if doesn't have a source attached - Most annoying problem is the back light stays on, so it's glowing. The other two displays go into power saving most properly. So far I have tried three different HDMI cables. I am trying to find the HDMI->DVI adapter that came with the mini so I can use that with a DVI->HDMI cable, but I'm assuming that's a passive adapter and nothing will change. I could not find any configuration options related to power savings, although I noticed when the display is connected to HDMI vs DP I have additional display options such as overscan control that seems to be more 'tv' related.