Hello. I'm happily using an HP ZR24W which has matching 1200 x 1920 res to my Imac. Why does HP want me to to connect DVI *AND* the USB? I'm using only DVI as my USB Imac ports are filled. Once in a great while, coming back from sleep mode, the HP screen turns to snow, but o/w no issue. Anyone know? Thanks. BTW, I don't use the new HP for gaming; just for more screen real estate.