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This compact unit accepts audio & video signals via an Hdmi or Dvi input and converts them into a Displayport signal. This allows or devices such as a Playstation 3 or Sky Hd box to be connected to high resolution monitors. Modern Thunderbolt equipped Apple displays (i.e. 27" display) can only support resolutions up to 720p Displayport/mini Displayport. This also applies to any converters/adapters. It appears these do not above their Dp Edid protocol, but protocol.