A data transmission system, comprising: a source device comprising: high-bandwidth transmitter circuitry; sideband transceiver circuitry; control circuitry to: generate a plurality of frames at one or more frame generation rates; provide the plurality of frames to the high-bandwidth transmitter circuitry; and disable at least the high-bandwidth transmitter circuitry responsive to entering a Panel Self-Refresh, PSR, operating mode; a sink device comprising: high-bandwidth receiver circuitry to receive the plurality of frames from the source device; sideband transceiver circuitry communicatively coupled to the source device sideband transceiver circuitry to form a low bandwidth side-channel communicative link; memory circuitry; control circuitry to: cause a storage of at least one frame included in the plurality of frames in the memory circuitry; and adjust a refresh rate of a communicatively coupled display device to the frame generation rate of the source device; characterized in that to maintain a temporal synchronization between the source device and the sink device through all or a portion of the PSR operating mode, the source device and the sink device are configured to use the low bandwidth side-channel communicative link for bidirectional communication of timing information between the source device and the sink device. a source device comprising: high-bandwidth transmitter circuitry; sideband transceiver circuitry; control circuitry to: generate a plurality of frames at one or more frame generation rates; provide the plurality of frames to the high-bandwidth transmitter circuitry; and disable at least the high-bandwidth transmitter circuitry responsive to entering a Panel Self-Refresh, PSR, operating mode; high-bandwidth transmitter circuitry; sideband transceiver circuitry; control circuitry to: generate a plurality of frames at one or more frame generation rates; provide the plurality of frames to the high-bandwidth transmitter circuitry; and disable at least the high-bandwidth transmitter circuitry responsive to entering a Panel Self-Refresh, PSR, operating mode; generate a plurality of frames at one or more frame generation rates; provide the plurality of frames to the high-bandwidth transmitter circuitry; and disable at least the high-bandwidth transmitter circuitry responsive to entering a Panel Self-Refresh, PSR, operating mode; a sink device comprising: high-bandwidth receiver circuitry to receive the plurality of frames from the source device; sideband transceiver circuitry communicatively coupled to the source device sideband transceiver circuitry to form a low bandwidth side-channel communicative link; memory circuitry; control circuitry to: cause a storage of at least one frame included in the plurality of frames in the memory circuitry; and adjust a refresh rate of a communicatively coupled display device to the frame generation rate of the source device; characterized in that to maintain a temporal synchronization between the source device and the sink device through all or a portion of the PSR operating mode, the source device and the sink device are configured to use the low bandwidth side-channel communicative link for bidirectional communication of timing information between the source device and the sink device. high-bandwidth receiver circuitry to receive the plurality of frames from the source device; sideband transceiver circuitry communicatively coupled to the source device sideband transceiver circuitry to form a low bandwidth side-channel communicative link; memory circuitry; control circuitry to: cause a storage of at least one frame included in the plurality of frames in the memory circuitry; and adjust a refresh rate of a communicatively coupled display device to the frame generation rate of the source device; characterized in that to maintain a temporal synchronization between the source device and the sink device through all or a portion of the PSR operating mode, the source device and the sink device are configured to use the low bandwidth side-channel communicative link for bidirectional communication of timing information between the source device and the sink device. cause a storage of at least one frame included in the plurality of frames in the memory circuitry; and adjust a refresh rate of a communicatively coupled display device to the frame generation rate of the source device; characterized in that to maintain a temporal synchronization between the source device and the sink device through all or a portion of the PSR operating mode, the source device and the sink device are configured to use the low bandwidth side-channel communicative link for bidirectional communication of timing information between the source device and the sink device.