I have connected everything, updated drivers etc, using C port cannot get 2 HDMI 4K TV screens running
one HMDI, one VGA
Any Help Harold
The CSV-1568 does not support 2 4K TVs
It shares the bandwidth of 16.2Gbps over all 3 of the display outputs.
Meaning if you attach 1 4K TV you have used all of it’s bandwidth. 4K need 15Gbps (assuming the TV is 4K60Hz 8 bits in color) Leaving 1.2Gbps.
|• When 3 Displays are connected – 16.2Gbps bandwidth will be shared|
|• Single Display Support – HDMI max 4K60Hz, DP Max 4K60Hz, VGA max 1920*1200 60Hz|
You might want to consider the CSV-1566.
16.2 Gbps is the bits on the wire. It uses 8b/10b encoding, so the actual data bandwidth is 12.96 Gbps.
To find the bandwidth used for each display, multiply the pixel clock with the bits per pixel (bpp).
bpp is bits per component (bpc) times 3.
bpc is usually 8 or 10 but can be as low as 6 in Windows.
bpc can be changed for AMD or Nvidia GPUs but probably not for Intel GPU.
One method to reduce bpp is to use chroma subsampling 4:2:2 (16 components per 8 pixels) or 4:2:0 (12 components per 8 pixels). This can reduce bpp down to at least 12bpp.
If the GPU supports DSC, then the bpp can be as low as 12 or even 8. For macOS, I know that 12bpp is the default DSC target bpp. I don’t know what DSC target bpp the Windows drivers for AMD or Nvidia use.
4K60 is 522.62 MHz pixel clock (using CVT-RB2 timing).
[email protected]: 4.18 Gbps.
[email protected] or 4:2:[email protected]: 6.27 Gbps.
[email protected] or 4:2:[email protected]: 7.84 Gbps.
[email protected] or 4:2:[email protected]: 8.36 Gbps.
[email protected] or RGB/4:4:[email protected]: 9.4 Gbps.
[email protected] or 4:2:[email protected]: 10.45 Gbps.
[email protected] or RGB/4:4:[email protected]: 12.54 Gbps.
[email protected]: 15.68 Gbps.
4K60 HDMI timing is 594 MHz.
6bpc has banding unless dithering is used.
8bpc is very difficult to detect banding.
10bpc is required for HDR (at least in macOS – not sure about Windows)
12bpc may be possible but I think it’s overkill so I didn’t include it.
4:2:0 has lower horizontal & vertical color resolution.
4:2:2 has lower horizontal color resolution.
DSC is visually lossless so it may be better than 4:2:0 and 4:2:2 at least for color.
DSC usually requires FEC which adds some overhead.
MST for multiple displays adds some overhead.
CSV-1566 only supports DisplayPort 1.2 so it doesn’t support DSC. But maybe that’s fine if your GPU doesn’t support DisplayPort 1.4 (pre 10th gen Intel CPUs).
You need to describe what model computer / GPU you have.
Intel UHD Graphics 620 is limited to DisplayPort 1.2 which has max 17.28 Gbps bandwidth to a USB-C dock that supports only USB 2.0 (Cable Matters makes such docks) or 8.64 Gbps to a USB-C dock that supports USB 3.x (which is the category that the CSV-1568 belongs to).
Also, DisplayPort 1.2 doesn’t support 4:2:0 or DSC.
So there’s no way for you to connect one 4K60 display to the CSV-1568, let alone two. The best you could get is one 4K30 display (actually, one 4K60 display may be possible using 4:2:2 8bpc at < 540 MHz but that might be difficult to achieve with Intel Graphics Command Center and the display would need to have support for that mode).
4K30 is between 257.66 MHz (CVT-RB2) and 297 MHz (HDMI 1.4). Two of them could work if they support 4:2:2 8bpc at < 270 MHz. I’m just not sure if the iGPU would output that mode. I would test with AMD or Nvidia GPU first.