Lindy 41047 video converter

HDMI/DVI-to-Mini-DP, 720p/1080p, HDCP, 5V DC This compact unit accepts audio & video signals via a HDMI or DVI input and converts them into a Mini DisplayPort signal. This allows HDMI or DVI devices such as a Playstation 3 or Sky HD box to be connected to displays such as the Apple Cinema Displays or a 27" iMac.

Important: Modern Thunderbolt equipped high resolution Apple displays (i.e. 27" display) can only support resolutions up to 720p via DisplayPort/Mini DisplayPort. This also applies to any video signal converters/adapters. It appears these Apple monitors do not support high resolutions above 720p via their DP EDID protocol, but only via Thunderbolt EDID protocol.