to HDMI1.2, and is sufficient for up to at 60Hz. In 2013, VESA released the Dual-Mode 1.1 standard, which added support for up to a 300MHz TMDS clock (9.00Gbit/s bandwidth), and is used in newer DisplayPort1.2 devices. This is slightly less than the 340MHz maximum of HDMI1.4, and is sufficient for up to at 120Hz, at 60Hz, or at 30Hz. Older adapters, which were only capable of the 165MHz speed, were retroactively termed "Type1" adapters, with the new 300MHz adapters being called "Type2". Dual-mode limitations Limited adapter speed Although the pinout and digital signal values transmitted by the DP port are identical to a native DVI/HDMI source, the signals are transmitted at DisplayPort's native voltage (3.3V) instead of the 5V used by DVI and HDMI. As a result, dual-mode adapters must contain a level-shifter circuit which changes the voltage. The presence of this circuit places a limit on how quickly the adapter can operate, and therefore newer adapters are required for each higher speed added to the standard. Unidirectional Although the dual-mode standard specifies a method for DisplayPort sources to output DVI/HDMI signals using simple passive adapters, there is no counterpart standard to give DisplayPort displays the ability to receive DVI/HDMI input signals through passive adapters. As a result, DisplayPort displays can only receive native DisplayPort signals; any DVI or HDMI input signals must be converted to the DisplayPort format with an active conversion device. DVI and HDMI sources cannot be connected to DisplayPort displays using passive adapters. Single-link DVI only Since DisplayPort dual-mode operates by using the pins of the DisplayPort connector to send DVI/HDMI signals, the 20-pin DisplayPort connector can only produce a single-link DVI signal (which uses 19 pins). A dual-link DVI signal uses 25 pins, and is therefore impossible to transmit natively from a DisplayPort connector through a passive adapter. Dual-link DVI signals can only be produced by converting from native DisplayPort output signals with an active conversion device. Unavailable on USB-C The DisplayPort Alternate Mode specification for sending DisplayPort signals over a USB-C cable does not include support for the dual-mode protocol. As a result, DP-to-DVI and DP-to-HDMI passive adapters do not function when chained from a USB-C to DP adapter. Multi-Stream Transport (MST) Multi-Stream Transport is a feature first introduced in the DisplayPort1.2 standard. It allows multiple independent displays to be driven from a single DP port on the source devices by multiplexing several