Apple discontinued the Thunderbolt Display production but i am able to buy a used one, though i need to know its compatibility with my imac 27 "2009 with mini display port cable .... would also like to know if it is possible to connect it with my pc with displayport cable or HDMI? and which cables i need for both situations? note that i am already connecting my imac to external monitor (Samsung UHD 27") through mini display port to display port cable