Does it support 2560x1440 at 60Hz and 2560x1440 at 144Hz? Old version of this adapter didn't support that.

USB-C Digital AV Multiport Adapter

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    This adapter has 50% more bandwidth than the previous adapter but only some computers can use the new bandwidth. Read the Apple Support document HT207806 "About the Apple USB-C Digital AV Multiport Adapter" to see if your computer is one of them. Basically, you need to be able to output a two lane DisplayPort 1.4 signal (though I don't know how some of the listed computers can do that).

    2560x1440 144Hz 8 bpc (bits per component) 4:4:4 or RGB (3 components per pixel) is too much bandwidth (604 MHz) for HDMI 2.0 (600 MHz) and this adapter has slightly less bandwidth (540 MHz) than HDMI 2.0.

    MHz is a measure of the pixel clock. The bandwidth increases with the pixel clock and also the number of bits per component and the number of components per pixel.

    You can increase max pixel clock to 648 MHz by reducing chroma subsampling to 4:2:2 (16 components per 8 pixels) while increasing color depth to 10 bpc.

    Note that 4K 60 Hz HDMI timing is 594 MHz so it also requires reduced chroma subsampling or reduced color bit depth with this adapter (most computers don't have a 6 bpc option though).

    Another option is to reduce blanking times so that pixel clock/bandwidth can be decreased for the same refresh rate. Displays require a certain amount of blanking time though. For example, some displays may accept a 4K 60Hz 533 MHz timing.

    If this adapter is not sufficient then search for one that does not include 5 Gbps USB 3.0 which will then allow four lanes of DisplayPort. For example, adapters that use the MCDP2900 chip will have four lanes operating at 5.4 Gbps per lane which gives them 33% more bandwidth than this adapter that uses a chip that has two lanes at 8.1 Gbps.

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